1985 Caddy Limo - Engine swap with transmission issues

[BlackBettyLimo]

Meet Black Betty, a 1985 Cadillac Fleetwood Brougham Limo. My buddy and I bought/ rescued her from an LA "hair band" recording studio where, before had she broke down, she had been in service for the last 20 years as the official party car for such bands as Slayer, Ratt, White Snake, Aerosmith, and Bon Jovi.

Like most party girls, she's pretty from afar, but far from pretty when you get up too close, or in daytime. Cheap paint, rust, broken sunroof, absolutely trashed interior. Everything you'd expect in a limo with real rock and roll history.

95969584
We bought her for $800 (plus $600 in back registration penalties) on the bet we could get her in motion for a few more grand. :popcorn:

We got two new batteries and replaced the rotted fuel lines and packed fuel filter, and darn if it didn't fire up. We limped around the block only breaking down twice. A tank of fresh gas, some spliced ignition wires (chewed by rats), general tune up, some speed runs to burn off the filth, and we had a wonderful party car that was always on the verge of overheating or breaking down.

While willfully ignoring the mountain of cash it would take to transform this thing into an enjoyable vehicle, it became apparent that the current head gasket leak wasn't going to fix itself, so in an alcohol induced fit of inspiration we decided to pull the motor and rebuild it. For anyone who has ever attempted such a thing you can see where this is going already. The OEM motor was a 4.1L TBI V-8 pumping out an aggressive 135hp. 0-60 was under 30 sec, wet. Obnoxiously underpowered for the task at hand it took about an hour into the tear down to decide to just go ahead do an engine swap. The engine was a total mess and after much research on the webs we found that we'd just be meticulously rebuilding one of the worst engineered GM motors in existence.

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Project funds are depleted and depression sets in. 1 year passes.

After some springtime beer-based research, and based on new budget constraints, we decided to buy an $800 1994 Buick Roadmaster with an 5.7L LT1 that had an output of 280p/ 335 lb-ft, paired with a 4L60E transmission. This seemed to be just enough grunt to pull a bunch of "adults" trying to cling on to their youth. The test drive went well, however on the hour-long ride home I noticed some water temp surging and hard shifts in the transmission.

6 months later and we finally get around pulling everything and scrapped the Roadmaster.

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I have zero fabrication skills so we found a guy that was going to help us with the engine mounts/ set pinion angle, etc. After putting us off for 4 months he decides to leave the country. :mad1:

5 more months pass.

While we were waiting to find a cheap and good (pick two, right?) fabricator, we decided to rebuild the motor and have the transmission inspected. It didn't make much sense to install an engine with known issues.

I had never rebuilt a pushrod motor before, and I'm a bit OCD when it comes to dirt, so it took me most of the summer just to clean the engine to be able to work on it. New water pump, oil pump, Optispark dist, main and cam bearings, rings, every seal I could find, de-carbonized, de-greased, heads were refreshed with valve job etc, etc. I didn't over-bore the cylinders, just deglazed with stones. The cam and crank were mostly in spec. I had hemorrhaged money on everything else so I decided to just let it be a loose engine. I figured I could run thicker oil, if necessary, and call it a day. It's not a hotrod and the mileage on it will be minimal.


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The engine rebuild took all summer, so in the meantime we got the transmission inspected/ refreshed. We were still waiting on a fabricator who wouldn't string us along or wasn't too busy. So the project sat for another 6 months.

We finally got some help though a very talented and generous friend and after a few more months got it in the vehicle.

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And now the transmission problem... more to come.

[dave w]

Thanks for sharing, keep us updated.:thumbsup:

dave w

[S3TPI]

Cool story!

[BlackBettyLimo]

Well, to my general amazement, I was not only able to successfully assemble a motor, but the thing actually started up on first crank and idled like a champ. No oil leaks, no spun bearings, no overheating. High fives all around.

Honestly, it's kinda an amazing feeling. If you haven't done it you should give it a try. Go slow, read the service manual a few times before you do the task at hand, and if you get in a bind, ask questions on forums and watch a youtube video or two (or 10, like I did).


https://youtu.be/j22UILXOqbA

So all excited like, we get her on the road, and she won't shift out of 1st gear, manually or otherwise.

We had taken the trans to a reputable shop so we were fairly confident that it wasn't a mechanical issue. But as we researched the 4L60E (electronically controlled) transmission we realized that when we unplugged the transmission harness and drove the car, the transmission was not flipping into a proper "limp mode." In theory, when you pull the power from the transmission it should default to 3rd gear and you should be able to manually select 2nd gear, and that was not happening. We were stuck in 1st gear.

We had also read on a forum that some people were able to spin first gear up to 3500 rpm, suddenly come off the gas, and feather it back in, and the trans would up-shift. We tried that, both while the trans had power and was unplugged, and this method worked in both instances. Ok, so, this now led us to believe that it may in fact be a mechanical problem. We pulled the trans and brought it back to the shop.

While they were checking it out we tested the VSS module (seemed ok), we Ohm tested all the wires from the PCM plug to the trans plug (they checked out), and we made sure that the transmission was getting a full 12v in the ignition key-on and running positions.

We also sent the PCM back to the guy who originally flashed it for us (to get rid of the digi-key requirement) and double checked the new/ different rear gear ratio and tire height he had set for the Caddy, and confirmed it was set for an automatic trans and not a manual one. It turns out some of his numbers were in fact off a bit and he re-flashed it to the new spec.

The word came back from the transmission guys that they went ahead and rebuilt the valve body, fully inspected every single part, replaced 3rd gear (was worn), and said "at this point any issue that may occur isn't going to be a mechanical one." This refresh was no cost to us, and so I’m fairly confident that at this point it’s not a mechanical problem.

We double checked all of our wiring and found that we had reverse wired the TCC wire to the brake switch.

So with all this in mind, we put it all back in the limo, and wouldn't you know, the dang thing still won't shift out of 1st gear.

The only change was when we now unplugged the transmission harness it did finally go into a proper limp mode (starts in 3rd gear and we could manually shift to 2nd). So I'm guessing there many have been some sort of mechanical issue originally after all.

HOWEVER, this still doesn't explain why when the transmission has 12v of power going to it, it won't shift out of first gear.

Now, up to this point we had been flying a bit blind. I had failed to pull the ALDL plug out of the Roadmaster and wasn't aware that there was software out there (aside from a GM tech tool) that could help diagnose some of this. We had no idea if the PCM was throwing relevant DTC codes at us or not.

Time to burn more money.

I found an ALDL plug on eBay and downloaded TSS Datamaster (demo version). I bought a ALDL to USB cable from John at 1320 Electronics, and he spent a good hour with me getting it working on my ancient PC laptop.Thanks John!

I started to monitor and according to Datamaster, it turned out we were initially only triggering (3) DTC codes: 43, 84 and 97

43 - This is an open or ground somewhere in the dual knock sensor wiring. I haven't been able to find anything that would suggest this would have any impact on the transmission, so I'm going to rule that out, unless anyone here has some knowledge to the contrary. It would seem odd to me that GM would basically cripple a car to 1st gear if the PCM lost knock sensor input.

84 - This is the transmission 3-2 control solenoid circuit. After I cleared all the codes a few times this is the only one that never came back. Not sure what triggered it, but it’s on my radar to keep an eye out for it again.

97 - This is an open or ground in the VSS output signal that goes to the digital speedo. The caddy has a mechanical speedo so this wire is obsolete unless we get an electrical to mechanical converter box. Based on my research this signal does not go back to the PCM, it’s purely output. We are receiving what looks to be correct MPH/ speed data to the PCM, as seen by Datamaster. So the VSS seems to be working as originally tested (we also replaced it with a brand new one to remove all doubt). I’ve read that we can add a resistor to this wire and it will remove the DTC code. If anyone has another opinion on whether or not this wire needs to be addressed in a different way, please let me know.

Ah, here are two other notes of odd behavior. When the car is in the key-on or running position the MIL light is lit up in a solid state. Also, when the car is running, both radiator fans turn on full blast. This happens when the car is cold or hot. When I clear the DTC trans codes the fans stop for a few seconds, then they both kick back on. Very odd.

While we were discussing my tech issues John suggested I check out TunerProRT (he sent me an .adx file, attached), and Scan9495.

I couldn't get Scan 9495 to work at the time due to some .NET framework stuff I didn’t have installed.

I loaded the supplied .adx into TunerProRT and unfortunately the data stream seemed all over the place. It was swinging from positive to negative numbers and wasn’t at all steady like the Datamaster data.

Being a total amateur with all this software I tried to make a few data logs (attached). For some reason I couldn't seem to log more than a +/- 15 seconds of data using Datamaster. If any one can help with this duration issue I’d greatly appreciate it. I've burned so many free-use licenses trying to learn the software that I only have a about 10 left.

I seemed to have better luck with the duration issue with TunerProRT, however the data seems to be junk (attached). If anyone has any insight as to what’s happening there, I’d greatly appreciate that as well.

Once I got home I downloaded the appropriate .net stuff. I’m happy to say that Scan9495 will now fully launch, but I’m away from the car so I haven’t been able to give that a try yet.

What I like about the 9495 software is that it looks like you can control the actuators, which will tell you if the transmission can receive a command signal. There seems to be a significant warning about not using that feature when the car is moving, so I’m a bit hesitant to try it without some wiser form of supervision. Perhaps it’d be best to track down a GM tech tool and operator?

Given that the Datamaster data was the only stuff I could observe/ trust, here’s what I observed:

- The PRNDL Flag value changes, the Gear Num value does not.

- Trans Modes A & B seem to alternate states when the PRNDL value changes. I’m not sure what this is indicating. i.e. If it's a command signal going to the trans or if it's an output status from the trans.

- 1-2 Shift Dlta T does not indicate a change at any time.

Unfortunately, that's all I know for the moment. I'm kinda stuck.

If anyone has any test methodologies you'd like me to try, using any of the mentioned software, I'll do my best to give it a go. Or if anyone can help me with the TunerProRT data issue that would be great as well.

I look forward to your collective thoughts.

Cory

[BlackBettyLimo]

I realize the above is a pretty big dump of complex info, but does anyone have any thoughts?
Thanks,
Cory

[dave w]

I realize the above is a pretty big dump of complex info, but does anyone have any thoughts?
Thanks,
Cory


I'm wondering about the PCM flash? Is the flash $EE or $EEB?

Can you post the .bin file that was flashed into the PCM?

I recently worked with someone who had the wrong flash in the LT1 PCM. With the correct flash, many headaches went away.

dave w

[BlackBettyLimo]

Thanks Dave, I just emailed the guy who flashed the PCM for that info. Do you know if there's a way to interrogate the PCM to tell if it's $EE or $EEB?

[dave w]

The PCM can be flashed either $EE or $EEB. It's a long shot the Flash is wrong, yet a likely cause of the headaches you posted.

dave w

[dave w]

I'm wondering about the PCM flash? Is the flash $EE or $EEB?

Can you post the .bin file that was flashed into the PCM?

I recently worked with someone who had the wrong flash in the LT1 PCM. With the correct flash, many headaches went away.

dave w

On second thought, lets ask for the stock unmodified .bin that was the used to start with. It might be sensitive topic with some PCM programmers, asking for a modified .bin file.

dave w

[BlackBettyLimo]

On second thought, lets ask for the stock unmodified .bin that was the used to start with. It might be sensitive topic with some PCM programmers, asking for a modified .bin file.

I'm told he doesn't save the .bin files, but that he does use $EE. "What's in there is the original with the emissions and vats deleted"

[dave w]

It was a long shot, so let's figure the flash is good.

I don't have any new ideas, just wanted to verify the flash.

dave w

[BlackBettyLimo]

It was worth a shot, thanks for the response either way!

The programmer says he can re-flash the PCM to remove the DTC codes (97 & 43). I'd probably want to keep the knock sensors in loop but it could be a good experiment to see if that quickly solves the issue.

I found a post that has a break down from a service manual as follows:

First Gear Range Only - No Upshift

Control Valve Body (60)


The 1-2 Shift valve is sticking
The spacer plate or gaskets are mispositioned or damaged


Case (103)
The case to valve body face is damaged or is not flat
Shift Solenoid Valves (366/368)


Stuck or damaged
Faulty electrical connection


2-4 Servo Assembly (13-28)


The apply passage case is restricted or blocked
Nicks or burrs on the servo pin or on the pin bore in the case
Fourth servo piston is installed backwards


2-4 Band Assembly (602)


The 2-4 band is worn or damaged
The band anchor pin is not engaged


Since the trans has been inspected/ rebuilt, twice, I'm not sure it's mechanical at this point, but I'm not ruling anything out.

I'm going to try and use Scan9495 tomorrow to see if I can trigger the actuators. Finger crossed.

[lionelhutz]

There are 2 solenoids that control the main shifting. They were referred to as A and B but then got called 1-2 and 3-4 to match the ODB2 convention. At any rate, the shift pattern is as follows.


A B
1st X X
2nd - X
3rd - -
4th X -


As you can see, if the A solenoid was stuck-on you'd get 1st and 4th gear, skipping any shifts into 2nd or 3rd gears. That pattern is also why "limp mode" goes to 3rd gear. No power to the solenoids and the transmission goes to 3rd gear.

Now, I'd expect you have to be doing around 30mph or possibly more before the PCM would command a shift into 4th gear. The speed really depends on the tune.

[lionelhutz]

Just to further note, I did check 5 bins and the lowest 3-4 upshift speed was 29mph.

Looking at your log and then a few of my old logs, the "Gear Num" in the left column of TTS is the actual commanded gear. Your log never changes from 1 so it's not even attempting to shift. In my old logs when I used TTS, that number would jump to the next gear and then I could see the rpm and slip rpm results due to the shift being commanded.

[dave w]

If you want, you can ship me your PCM, I can then read and post the .bin file I read from the PCM.

I only ask that you pay shipping, both ways.

Send me a PM for my shipping address.

dave w

[BlackBettyLimo]

First off thanks for the continued responses and offers for help, I'm feeling much less alone in this battle! :thumbsup:

I spent a good part of the day trying to sort out some of the above and here's where I netted out:

Knock Sensors - Per the service manual, attached
1. I tested both knock sensors and they came back within the correct resistance spec.
2. I ohm tested the wires from both plug ends (each sensor plug to PCM connector) and they checked out ok.
3. I put the car in key-on position, pulled off the PCM connector and tested the corresponding pin on the PCM itself for 5V and there was nothing. Then I plugged the connector back in and tested the same pin by using a piece of thin wire running down through the back side of the connector, still nothing.

The service manual says there should be 5V. If not, there's a circuit short or it's a bad PMC.
So that points to bad PCM?


Scan9495 - Data logging

Wow, this software is really great, I'll certainly make a donation! That said, for the life of me, I couldn't figure out how to record and save the transmission data. I checked the box in the transmission tab for dataloging, but i couldn't play it back. All of the datalogs I made today can be found here (the last one is probably the best): https://www.dropbox.com/sh/84hyxymk0d4mn1y/AABx1DZQEGACZUdQFtnKj3Rba?dl=0

Because I couldn't playback the trans data I made a video (https://youtu.be/ARK0Uh2pCxs) which should match the last of the data files in the dropbox if you sort by date/ time. I apologize in advance for the video quality. I'll try to stabilize it later when my computer isn't acting up.

The software seems to create two files (DLOG-trans... and DLOG-Save...). I can't open the "trans" file without getting a hex error. The "Save" files open but do not play back the transmission data. Confused yet? I am.

Transmission Observations

I jacked up the tail of the car and did the following:

1. (not in video) When shifted in Park and key-on, I was able to use the Actuator screen feature to actuate all the solenoids one at a time, in both directions. Or at least, I was able to hear them all make a clicking sound.

2. If you watch the video, towards the end, you'll see that I am able to use the command shift buttons to shift gears up and down successfully. You'll also see that sometimes I had to click more than once to get it to work, not sure if that's an indicator of anything.

3. Manually shifting the transmission does NOT change the gears.

Thoughts/ Questions

Given that the knock sensor 5V output pin on the PCM does not work, I'm led to believe I may want to replace the PCM.

I'm not sure what it means if I can command the transmission to shift up and down using 9495, but it refuses to shift manually.

Is that a PCM problem? i.e. The PCM is not sending the proper signal to the transmission.

Or the it a mencanical issue? i.e. The trans is in a mechanical state which will ignore an incoming signal.

Any thoughts?

[BlackBettyLimo]

There are 2 solenoids that control the main shifting. They were referred to as A and B but then got called 1-2 and 3-4 to match the ODB2 convention. At any rate, the shift pattern is as follows.


A B
1st X X
2nd - X
3rd - -
4th X -


As you can see, if the A solenoid was stuck-on you'd get 1st and 4th gear, skipping any shifts into 2nd or 3rd gears. That pattern is also why "limp mode" goes to 3rd gear. No power to the solenoids and the transmission goes to 3rd gear.

Now, I'd expect you have to be doing around 30mph or possibly more before the PCM would command a shift into 4th gear. The speed really depends on the tune.

Thanks for this! I was paying close attention to these cells in Scan9495 because of you.
If you watch the video I just posted you can see these cells in action.
When I manually shift these cells/ solenoids both stay on. When I "command" it to shift up and down they operate as they should.

[BlackBettyLimo]

Just to further note, I did check 5 bins and the lowest 3-4 upshift speed was 29mph.

Looking at your log and then a few of my old logs, the "Gear Num" in the left column of TTS is the actual commanded gear. Your log never changes from 1 so it's not even attempting to shift. In my old logs when I used TTS, that number would jump to the next gear and then I could see the rpm and slip rpm results due to the shift being commanded.

Yes, the PCM is failing to send a command signal. Not sure why at this point. Electrical or mechanical?

[BlackBettyLimo]

If you want, you can ship me your PCM, I can then read and post the .bin file I read from the PCM.

I only ask that you pay shipping, both ways.

Send me a PM for my shipping address.

dave w

Thanks of the generous offer Dave, Much appreciated. Let's get some thoughts on my latest post before we move to that. Maybe I'm throwing time and money at a bad PCM at this point?

[kur4o]

I think the problem might be related with the ParkNeutralPosition switch located on the shift lever.
If it is not installed properlly the pcm will thinks the car is in P or N and will never attempt to shift.

[BlackBettyLimo]

I think the problem might be related with the ParkNeutralPosition switch located on the shift lever.
If it is not installed properlly the pcm will thinks the car is in P or N and will never attempt to shift.

Is that switch not located in the transmission itself? As you can see in the video link above the trans data shows the gear selector moving, although it is not commanding a gear change.

[kur4o]

It is located at the shift lever. It goes to pin C15 at PCM.
You can check where those wire goes and see if it is connected somewhere.
For the PCM to think it is in P or N the wire must be grounded.
If the wire is in open state or not connected It is very possible an error is set and PCM is in some service mode.

[kur4o]

OK I just watch the video.
The PNP switch is mostly related with IAC valve so it`s not very important for the not shifting problem.
I just check could the trans solenoids can be manually commanded if the bin is for manual transmission.
Answer is yes, so my final guess is, you have bin for manual transmission in the PCM.
On the video everything look OK except for the transmission not shifting.

[BlackBettyLimo]

OK I just watch the video.
The PNP switch is mostly related with IAC valve so it`s not very important for the not shifting problem.
I just check could the trans solenoids can be manually commanded if the bin is for manual transmission.
Answer is yes, so my final guess is, you have bin for manual transmission in the PCM.
On the video everything look OK except for the transmission not shifting.

The guy who originally flashed the PCM though he could have made that error, so I sent it back to him and he confirmed all the correct specs and made sure he had a flash for an automatic transmission (he suggested that as a possible issue).
I'm guessing he triple checked his flash this last time.

I still need to go see about pin C15 next time I'm at the car, just for grins. No codes being thrown at the moment for that.

[lionelhutz]

I'm certain I have the P/N switch C15 open and the brake switch C14 input jumpered to power and my transmission works.

I recall something about the Manual/Auto flag that is identified in the $EE was wrong because it was giving the wrong results with some bins. I wouldn't turn-on the auto in a bin but rather start with an auto bin.

I'd think the tuner would have pulled the bin, turned-off the stuff which was removed and then re-flashed the same bin.

[kur4o]

Since you have a working cable, download winflash programm from tunercats here:

http://tunercat.com/software/winflash/flash_setup.exe

It is fully working demo version limited to one month of usage.
Read the bin from your PCM and post it here.
That way we can help you really fast.

[BlackBettyLimo]

Since you have a working cable, download winflash programm from tunercats here:

http://tunercat.com/software/winflash/flash_setup.exe

It is fully working demo version limited to one month of usage.
Read the bin from your PCM and post it here.
That way we can help you really fast.


Ah, great! Thanks,will do!

[BlackBettyLimo]

Since you have a working cable, download winflash programm from tunercats here:

http://tunercat.com/software/winflash/flash_setup.exe

It is fully working demo version limited to one month of usage.
Read the bin from your PCM and post it here.
That way we can help you really fast.

I was able to pull the bin file using Tunercat's Winflash as suggested, attached.
What's the best way to view this file?

[BlackBettyLimo]

I'm certain I have the P/N switch C15 open and the brake switch C14 input jumpered to power and my transmission works.

I recall something about the Manual/Auto flag that is identified in the $EE was wrong because it was giving the wrong results with some bins. I wouldn't turn-on the auto in a bin but rather start with an auto bin.

I'd think the tuner would have pulled the bin, turned-off the stuff which was removed and then re-flashed the same bin.

Thanks for the input on C14/15!

The guy who did my flash seems very competent so I'm guessing that outside of any major oversight his methodology is sound.

Is there a way to find a OEM bin and compare the two files?

If I do have to adjust the bin file, I should turn off anything related to Air Conditioning since the limo's AC controls will operate this independently of the PCM. This may fix my "fans-are-always-running on high" issue, based on some recent research.

I should also turn off the VSS output signal.

The fact that the pin on the PCM for the knock sensor circut doesn't register 5v is still of some concern...

[kur4o]

I checked the bin.
On eside part, the data is not defined properly on the current xdf files. It looks like tside is $ee and eside is $eeb or something else.
The point is any change on the eside calibration will have unpredictable result.
The best way will be to start with the latest bin for your application. Based on tis2web, your starter bin will have p/n 16200271.
Unfortunatelly I could`n find it anywhere, so we need to pick you another bin similar to your application.

Can you please post your final gear ratio and tire size so I can make you a suggestion.

[BlackBettyLimo]

I checked the bin.
On eside part, the data is not defined properly on the current xdf files. It looks like tside is $ee and eside is $eeb or something else.
The point is any change on the eside calibration will have unpredictable result.
The best way will be to start with the latest bin for your application. Based on tis2web, your starter bin will have p/n 16200271.
Unfortunatelly I could`n find it anywhere, so we need to pick you another bin similar to your application.

Can you please post your final gear ratio and tire size so I can make you a suggestion.

thanks for checking it out! I have to apologize and advance as the vocabulary is starting to get a bit over my head. I'll have to look up eside and tside so I can track this conversation.

Rear gear should be 3.42

Tires are 28" (235/75R15)

[BlackBettyLimo]

I checked the bin.
On eside part, the data is not defined properly on the current xdf files. It looks like tside is $ee and eside is $eeb or something else.
The point is any change on the eside calibration will have unpredictable result.
The best way will be to start with the latest bin for your application. Based on tis2web, your starter bin will have p/n 16200271.
Unfortunatelly I could`n find it anywhere, so we need to pick you another bin similar to your application.

Can you please post your final gear ratio and tire size so I can make you a suggestion.

Per the site (at bottom of page) : http://fbodytech.com/bin/index.html


16200271 may have been superseded by 16230201?

[kur4o]

You can try with this bin, should be a close match.
I turned off vats, so it`s ready for burning.
If it corrects your problem other stuff can be done later.

How do you measure the 5volt on knock sensor circuit with sensor attached or with the sensor disconnected.
It will read 5 volts only if it is disconnected and ignition must be turned on.

[kur4o]

Per the site (at bottom of page) : http://fbodytech.com/bin/index.html


16200271 may have been superseded by 16230201?

You`r right 16200271 is your current bin and 16230201 is the latest bin based on the vin number.
16230201 is not available online also.

[BlackBettyLimo]

You can try with this bin, should be a close match.
I turned off vats, so it`s ready for burning.
If it corrects your problem other stuff can be done later.

How do you measure the 5volt on knock sensor circuit with sensor attached or with the sensor disconnected.
It will read 5 volts only if it is disconnected and ignition must be turned on.

Thanks for the bin! I'll try to get out there in the next day or two and give it a go.

I followed the diagnostics for the knock sensor in the attached PDFs a few posts up.
I tested each sensor for resistance, and they checked out.
I ohm tested all the wires with both ends detached (at PCM and at knock sensor).
I tested for voltage at the knock sensor connectors with PCM plug connected and key on, there was no voltage present. With connectors at knock sensors detached, and connector attached to PCM, I stuck a wire through the backside of the PCM connector and tested for voltage with key on, no voltage found.
I unplugged the same PCM connector and tested the pin directly in PCM with key on, and there was no voltage found.

Unless it is some sort of bin related issue, it seems that circuit is dead within the PCM?

[BlackBettyLimo]

You`r right 16200271 is your current bin and 16230201 is the latest bin based on the vin number.
16230201 is not available online also.

Thanks for clarification, I'll post on a few other forums and see if there's a shot at finding it.

I couldn't find anything online regarding eside and tside. If it's not a pain, can you give me a short description of what those two sides of the bin file represent?

[kur4o]

As you know PCM has two flash chips 64kb each. BIN is split between the two chips. Each chip has its own operating system, cal data and processor. Like two separate computers in one box.
Eside chip is responsible mainly for engine operation, Tside for transmission operation.
I hope that makes it a little more clear.

It is bad you don`t have 5v ref on the PCM knock circuit. It could be due to flash, or the PCM might have internal problems and needs replacement.
You can try flash the bin I posted and if there is no improvement look for another PCM.

[lionelhutz]

That tune appears to be $EEB on the engine side but its just plain hosed in the transmission tables. Neither $EE or $EEB shows transmission data that makes any sense. The 1-2 shifting is 30mph with no throttle and just goes higher as the %tps increases. No wonder it wouldn't shift.

You could try Steve's Robotune to create a tune to match what you have.

http://fbodytech.com/index.html

Read the rest of Steve's info because its good stuff. The CPP disabling has to be done right or you hurt proper BLM operation.

[BlackBettyLimo]

As you know PCM has two flash chips 64kb each. BIN is split between the two chips. Each chip has its own operating system, cal data and processor. Like two separate computers in one box.
Eside chip is responsible mainly for engine operation, Tside for transmission operation.
I hope that makes it a little more clear.

It is bad you don`t have 5v ref on the PCM knock circuit. It could be due to flash, or the PCM might have internal problems and needs replacement.
You can try flash the bin I posted and if there is no improvement look for another PCM.

Thanks for the quick primer, that's very helpful info. I wasn't aware of the two separate chipsets, etc.

[BlackBettyLimo]

That tune appears to be $EEB on the engine side but its just plain hosed in the transmission tables. Neither $EE or $EEB shows transmission data that makes any sense. The 1-2 shifting is 30mph with no throttle and just goes higher as the %tps increases. No wonder it wouldn't shift.

You could try Steve's Robotune to create a tune to match what you have.

http://fbodytech.com/index.html

Read the rest of Steve's info because its good stuff. The CPP disabling has to be done right or you hurt proper BLM operation.



Thanks for taking a look. I wonder where the file got hosed in the process. I sent him the PCM for the initial flash (VAT removal etc), then sent it back to him confirm his work when I found the shifting issue. He did tell me he made a 2nd adjust to the bin (tire and rear gear) and re-flashed it. He swears he pulls the OEM bin and only makes the basic deletions (and uses $EE). Odd.

I'll take a look at Steve's site, looks interesting. The ran the robot tune and it suggested bin 16210011. Hard for me to tell what the differences are from my base file. If I wanted to take a look at the bin file myself and start learning some of this stuff, would I use TunerCat (OBD1 Tuner) and purchase the $EE definition file? Or do I need GM Tech1 tools to delete VAT, AC, etc.

I've only played with VE, Advance and O2 tables when I had my Electromotive Tec II for my other project car, but this GM stuff gets in to the technical weeds pretty fast!

I googled CPP and it seems to apply to a clutch switch? Is this related to TCC or a manual transmission? (or did you mean CCP?)

Sorry, lot's of technical blindspots here, but I'm trying to get up to speed quickly.

[BlackBettyLimo]

Update: I just found a '94 Roadmaster PCM on eBay and bought it. Ha, I'm finally running out of patience (It's a 2 hour drive round trip every time I go work on the car) and that knock sensor circuit is on my mind.

Brad from Garret Tuning is the eBay seller and mentioned he's a member here. I'll download the stock bin and donate it to the database of clean OEM files before I modify it.

It would be interesting to do a bin compare with my current file and see just how hosed it is.

For grins, I'll try uploading the bin Kur4o supplied to my existing PCM if I can get to the car in the next few days.

[lionelhutz]

Sorry, CCP.

I used CATS to view it using both the $EE and $EEB definitions.

On Steve's site the second thing down is a $EE Tunerpro definition file. You can use it with Tunerpro. A small tip, In the left side parameter tree box chose Parameter Category from the drop-down. Part of Steve's work was to categorize the parameters so you want to use that view. This only does $EE so you can't look at your bin right but check out the normal mode up/down shift points because that table was similar in both $EE and $EEB. You can see how the 1-2 shift only happens at a high speed.

This thread does have a $EEB definition for Tunerpro but I have no idea how good it is since I have no need to use it.

http://www.gearhead-efi.com/Fuel-Injection/showthread.php?335-16188051-and-16181333-PCM-Information-EE-EEB

[BlackBettyLimo]

You can try with this bin, should be a close match.
I turned off vats, so it`s ready for burning.
If it corrects your problem other stuff can be done later.


Hey kur4o, I'm sure this is somehow user error on my end since I'm just wrapping my head around TunerPro, but I just opened your bin file (using Steve's EE definition file) and I'm seeing the Flags "VATS Enable" and "VATS Diagnostic (Error 46)" as still being "set." i.e. The check box is checked.

Am I reading that right?

[BlackBettyLimo]

Sorry, CCP.

I used CATS to view it using both the $EE and $EEB definitions.

On Steve's site the second thing down is a $EE Tunerpro definition file. You can use it with Tunerpro. A small tip, In the left side parameter tree box chose Parameter Category from the drop-down. Part of Steve's work was to categorize the parameters so you want to use that view. This only does $EE so you can't look at your bin right but check out the normal mode up/down shift points because that table was similar in both $EE and $EEB. You can see how the 1-2 shift only happens at a high speed.

This thread does have a $EEB definition for Tunerpro but I have no idea how good it is since I have no need to use it.

http://www.gearhead-efi.com/Fuel-Injection/showthread.php?335-16188051-and-16181333-PCM-Information-EE-EEB

I downloaded Steve's EE file and I believe I was able to fully open my bin in Tuner Pro. I see what you're talking about. The other bin Kur4o supplied seem to have much more reasonable data values in that table.

How did you determine that the eside and tside data may be $EEB? Is that something I can view in TunerPro? Does that involve the bin stacker/ splitter feature?

[lionelhutz]

Check Injector flow rate which should be around 24lb/hr and cylinder volume which should be 717ml/cylinder for a 350. I can't recall offhand, but one shows as 0 when you open an $EEB bin using a $EE definition. I think the other one also shows too high a number.

[kur4o]

It is not changed, glad you notice it on time.
I hate tunerpro with its triple save bin feature, so sorry about that.

Will upload fixed bin soon.
Do you need any other features changed.

[kur4o]

fixed bin

[BlackBettyLimo]

fixed bin

Thanks! I'll give it a swing.

I've started making a master list of all the things I'll need to turn off (or confirm off):

VATS
A/C
Traction Control
Oil Life
Oil Level
VSS Output
Air Pump
Corvette related items (should be off by default)
Skip Shift Enable (should be off by default)
Speed Density Enable (should be off by default)
Shift Light Diagnostic (should be off by default)
Transmission Slip (should be off by default)
CCP Enable at Low TPS (should be off by default) - This came up in prior posts. Researching.

Should I turn off the following?:
EGR - Mine functions but I'm not sure if this needs to be turned off if other emissions items are disabled (air pump, etc)
"Transient" Fuel Routine - This came up in prior posts. Researching.

Anything I'm missing?

[kur4o]

From the list you need to turn off only AC and VSS output errors and oil life and level errors if are enabled.

If you`ve removed Charcoal canister from engine. Turn off CCP error and plug the hole.
If you leave the valve just make sure it`s plugged and cable is attached.
Don`t touch egr if it`s in working order and leave transient fuel enabled.

[lionelhutz]

Code 97 is the VSS output I believe with 24 being the one for the sensor.

When you remove the CCP solenoid you don't disable the transient fuel routine. You can turn-off the code and leave the PCM still attempting to purge the canister even though it's not doing anything useful. The side effect is that the fueling is wrong during CCP operation. Or, you can also set the CCP Enable - Min Coolant Temp to max and the Special BLM Cells - Enable Max CCP% to minimum. The side effect is the PCM no longer uses the special BLM cells. The point is don't just turn the CCP Enable - Min Coolant Temp to maximum thinking that disables the CCP because this locks the PCM into using the special BLM cells.

Does the Limo have a charcoal canister? If it does, then hook the purge line from the canister to the CCP solenoid and do nothing in the programming.

[BlackBettyLimo]

Check Injector flow rate which should be around 24lb/hr and cylinder volume which should be 717ml/cylinder for a 350. I can't recall offhand, but one shows as 0 when you open an $EEB bin using a $EE definition. I think the other one also shows too high a number.

Wow, yeah this bin file is way out of whack...

[BlackBettyLimo]

From the list you need to turn off only AC and VSS output errors and oil life and level errors if are enabled.

If you`ve removed Charcoal canister from engine. Turn off CCP error and plug the hole.
If you leave the valve just make sure it`s plugged and cable is attached.
Don`t touch egr if it`s in working order and leave transient fuel enabled.

We transplanted the Roadmaster's CCP into the Caddy, so barring any dumb installation errors we should be good.

Noted regarding EGR and Transient fuel. Looks like the original bin in the PCM had CCP, EGR and Transient Fuel all turned off.

[BlackBettyLimo]

Code 97 is the VSS output I believe with 24 being the one for the sensor.

When you remove the CCP solenoid you don't disable the transient fuel routine. You can turn-off the code and leave the PCM still attempting to purge the canister even though it's not doing anything useful. The side effect is that the fueling is wrong during CCP operation. Or, you can also set the CCP Enable - Min Coolant Temp to max and the Special BLM Cells - Enable Max CCP% to minimum. The side effect is the PCM no longer uses the special BLM cells. The point is don't just turn the CCP Enable - Min Coolant Temp to maximum thinking that disables the CCP because this locks the PCM into using the special BLM cells.

Does the Limo have a charcoal canister? If it does, then hook the purge line from the canister to the CCP solenoid and do nothing in the programming.

I think I'm following you on the CCP stuff. Since I transplanted the canister I should ok to leave everything as is (edit: more like the file Kur4o has supplied). I should probably test the CCP solenoid to see if it's working properly.

Regard VSS, yes, I'm only disabling the Output (error 97), but leaving the one for Error 24 set to on.

[BlackBettyLimo]

Kur4o, Here's my attempt at further adjusting your bin file in TunerPro, attached.

Here's the log that seems to be saved along side the bin file:
10/14/2015 22:36:22 Flag: Vss Signal Diagnostic (Error 97) changed from Set to Not Set..
10/14/2015 22:42:52 Flag: A/C Press Sensor Diagnostic (Error 66) changed from Set to Not Set..
10/14/2015 22:42:57 Flag: A/C Press Sensor Diagnostic (Error 67) changed from Set to Not Set..
10/14/2015 22:43:01 Flag: A/C Relay Diagnostic (Error 68) changed from Set to Not Set..
10/14/2015 22:43:05 Flag: A/C Clutch Diagnostic (Error 69) changed from Set to Not Set..
10/14/2015 22:43:10 Flag: A/C Clutch Relay Diagnostic (Error 70) changed from Set to Not Set..
10/15/2015 00:08:59 Flag: Fan 2 Diagnostic (Error 78) changed from Set to Not Set..
10/15/2015 00:11:11 Flag: Oil Level Diagnostic (Error 96) changed from Set to Not Set..
10/15/2015 00:11:15 Flag: Oil Life Diagnostic (Error 95) changed from Set to Not Set..

I also ran the Difference Tool and noticed that the T-side Checksum had also changed (from 42CO to 428C) for some reason. Since I used your file as the base I'm not sure what would make that shift. I didn't touch that parameter.

Any ideas?

[lionelhutz]

The checksum changes any time you make a change. It's a check calculated using the rest of the bin to ensure the bin is valid.

[BlackBettyLimo]

The checksum changes any time you make a change. It's a check calculated using the rest of the bin to ensure the bin is valid.

Ah, got it. Thank you!

[BlackBettyLimo]

Gentlemen,

You have succeeded in helping yet another wretched soul, such as myself, solve the mysteries of their technical shortcomings.

The limo shifts! Thank GearHead EFI, it shifts.

I trekked out to the car today armed with the adjusted Kur4o file ("fixed_plus", above), a new/ used PCM, and a lot of crossed fingers.

First, I uploaded the new bin onto the old PCM, and took the car for a quick test run. Within 15 feet I could feel 2nd gear shift (a bit abrupt) and within 40 feet 3rd gear hit (very smoothly). I was datalogging with Scan 9495 and could see the Commanded Gear cell change as it should. All manual shifts worked correctly and smoothly. On the road she felt great with good solid power. For the first time the limo felt very light with all that new torque.

I did notice while I was datalogging I was still getting the Knock Sensor code 43, and was also getting Evap Canister code 26. But hey the car was actually moving down the road for the first time in 3 years! :rockon:

When I got back to the garage I swapped out the old PCM of the new one, and uploaded the new bin file once again.

The 2nd test drive went well, for a bit. As I was coming back up a very long and steep hill the car began to lose power and snort a bit, shifting was very weird. Thankfully I was able to limp it back to the garage and after a few minutes I realized I must have been running out of gas. The Fuel Gauge is a bit off since we swapped gas tanks/ sending units. Luckily I had an extra 5 gallons sitting around, so I gassed it up and took it for another spin.

Performance was thankfully back to normal, but the only problem was I was still getting Knock Sensor code 43 and Evap Canister code 26.

I tested the pin for the knock sensor on the PCM connector, and found it had 5 volts. This is at least is better than the old PCM, but still have no idea why the code is being thrown given that I've tested all of the sensors and wires and they are "ok." :mad1:

I think I figured out the Evap Canister code, but that may be a deeper issue which I'll post later.

In the meantime I thought you guys would enjoy some good news for once! She runs!

Sincerely, kur4o and lionelhutz, thank you for all the help. PM me the name/ location of your favorite local bar and you'll have a few rounds waiting for you on your next visit! Seriously.

Cory

[1project2many]

LOL... So you're going to go out and party like a rock star??

[BlackBettyLimo]

LOL... So you're going to go out and party like a rock star??

Haha, not quite yet. It's a pretty long punch list before we can celebrate, but looking forward to the day.

[kur4o]

Wow, great we managed to help you out. I am really happy.
You can check the knock sensor voltage at the pcm, using tunerpro and the attached adx file.
Adx is based on the Eaglemark great EE adx, with some small modifications by me.

[1320_john]

Congrats on getting the caddy back on the road!

[jthompson122183]

Wow, great we managed to help you out. I am really happy.
You can check the knock sensor voltage at the pcm, using tunerpro and the attached adx file.
Adx is based on the Eaglemark great EE adx, with some small modifications by me.

sorry to invade the thread. Kur4o, i gave your mod.adx a go, it connects to the pcm, but couldnt get anything to show up on the tp dashboard. same with engine data list. i have no problems with the original 16188051 3.8.adx

[BlackBettyLimo]

I hope you guys don't mind my long rambling updates, because here's another one.

Now that I finally have some major progress on the car I was hoping it would be a little less painful to go work on the thing, but as it turn the hits keep on hitting.

I had a chance to get out there on Saturday to take another short victory drive and try to sort out the remaining error codes: Knock 43 and CCP 26

I figured the first step was to question everything that I personally didn't do myself, and then question everything I did do myself. We are all fallible, and there's been many different hands working on this project.

As my buddy read out loud the pin location and color of wire of in each PCM connector it came very clear very fast what was going on. The harness is a total mess.

The guy who did my original PCM flash was also the guy who did my harness so it was logical that I might point a finger that way.

After the car was shifting I did call him and tell him about the junk bin file that was preventing the car from shifting and he swears up and down that it was the same bin he pulled off the PCM, and that he only made adjustments to the rear gear, tire info, VAT, etc. We are going to have to agree to disagree on that one. Somehow the bin got scrambled in his care. The PCM came out of a running vehicle that ran/ shifted, I sent it to him, and I got back a messed up bin.

But since I'm doubting his flash, I began to fully doubt his harness.

After a day of reading wiring diagrams and checking things out. Here are the findings:

Red PCM Connector Cavities
9 - EGR Vacuum Control Valve Relay Solenoid Control - This should be a grey wire, but is green/ white for some reason. I haven't chased down where this goes yet.
14 - Secondary Air Injection (air) Pump Relay Control - Missing wire
25 - Fuel Enable - Missing wire

Black PCM Connector Cavities
1 - A/C Signal request signal - Wire missing
8 - VSS output - Wire missing
11 - "Low Oil Level" Indicator - Wire missing
13 - Transmission 3-2 Control Solenoid - Should be a brown wire, but is white for some reason. I haven't chased down where this goes yet.
21 - A/C Clutch Status - Wire missing
22 - TCC Temperature Switch Signal - Wire missing
26 - Power Steering Pressure Switch - Wiring missing
27 - Engine Oil Level Sensor - Wire missing

Clear PCM Connector Cavities
15 - PNP Signal - Wire missing

Blue PCM Connector Cavities
8 - A/C Clutch Control - Wire missing
9 - MIL (Service Engine Soon) Control - Plastic retainer clip for pin connector is broken/ missing and the entire connector is totally epoxied closed so I can't swap pin 21/22, below, pic attached)
10 - Evaporator Canister Purge Solenoid Valve Control - Wire missing
12 - A/C Refrigerant Pressure Sensor Signal
16 - "Change Oil" Indicator Control
22 - Knock Sensor Signal - Wire missing, found it swapped into cavity 21 instead for some reason .

Other notable things
The wires for the EGR has a CCP plug grafted on the end, and has been plugged in to the CCP Solenoid this entire time.
The EGR is not hooked up at all.

Oh man.

So at this point I need to point the finger at myself and note the largest error I've made in this whole project, which is: Not taking an informed/ leadership position on this project.

I didn't do the research, so I didn't know what to ask for, or what to expect. I hoped I could hire my way around my blind spots and let people sort it out for me.

I called the guy who did my harness/ PCM once again and he said the same thing that he said about the PCM. "The harness you gave me is the one you got back. I don't remove wires from PCM connectors or change plugs from one circuit to another (CCP to EGR). Don't know what to tell you."

As much as I'd like to get pissed at someone, I just have to blame myself. I honestly don't know what harness I sent him. I though it was an OEM harness because I thought I'd bought a stock Roadmaster. In retrospect, I never bothered to inspect the harness before I sent it away. The original guy who helped me take out the motor just lopped off wires without labeling them (at the time we though he was going to finish the swap, but didn't). We took it straight off the engine threw it in a box and shipped it out.

Maybe the guy set me a junk harness back, maybe I sent it to him.

Some major lesson learned there, but I also learned some lessons about looking closer at the details of my own work.

It's become clear that when I was first testing the knock sensor wire on the PCM connector I didn't count out the pin position of where the wire should have been. I just found the dark blue wire in that row, assumed it was in the correct pin position, and tested it as dead (which by the way, cavity 21 should be dead). As it turns out pin 22, in the correct position, does have 5V at it after all. So the original PCM's knock circuit is not bad. If I had taken my time and paid more attention to detail I wouldn't own a 2nd PCM I bought for $138 for no apparent reason. Hurray. Mistakes in methodology cost money.

Also, I'm not sure how I didn't notice the EGR wasn't hooked up, at all. It's buried under a bunch of wires and it looked like it had a plug in it. My fabricator who helped with the motor mounts is the one who helped finish up wiring the car and I'm sure if he didn't find a plug for it he just assumed I had deleted it. I assumed there was a plug and it was hooked up. Probably should have looked closer...

The really odd one was finding out that someone put a plug for the CCP on the EGR wires (pic attached). That's just plain weird. If anyone has a possible theory as to why, I'd love to hear it. I'm baffled.

All of the other missing or swapped wires are somewhat irrelevant at this point. I just bought another LT1 Harness and will make my own from scratch, and double check my own work, twice.

In some ways I'm relieved that at least the DTC code mystery is now solved. Fixing this harness should get the knock sensors, EGR, and CCP up and running again.

I may even fender mount the air injection pump and see if I can get that system working. I'd love to be able to properly smog this thing (good old California).

Lastly, if I can figure it out, it may be good to have the Caddy's A/C system monitored by the PCM. Not sure if that's possible or what that would take but might be worth looking in to it.

That's it for now. Parts are on there way.

Learn from my mistakes!

[BlackBettyLimo]

Wow, great we managed to help you out. I am really happy.
You can check the knock sensor voltage at the pcm, using tunerpro and the attached adx file.
Adx is based on the Eaglemark great EE adx, with some small modifications by me.

Thanks of the file! Hopefully I'll be able to check it out before I leave town!

[BlackBettyLimo]

Congrats on getting the caddy back on the road!

Thanks! As you'll read the fight isn't over just yet. But I'm closer than ever!

[kur4o]

Adx is set to show only mode 01 msg 03 data at the item list.
This mode is used for diagnostics. It shows pcm voltages and switches status.
If you change the settings it can show all the data but the data refresh rate will be really slow.
To show the engine data change CONNECTION COMMAND to engine connection and MONITOR COMMAND to engine data.
Can I ask you to make a log with the adx as is. Start recording the log at IGNITION on, then start the engine, run the engine for some time and save the log.

[1project2many]

How much work was it to install that harness? It can be much tougher to chase mistakes than to begin again...

If you're going to chase down errors I'd recommend starting with the ecm pinout and checking each wire one at a time. Mark down good/bad/notes on a separate notepad and if necessary only do a few circuits each night. I would probably divide the job into "check and report" and "repair" tasks to get a good idea of just how much work is to be done. If four wires are in wrong locations and you pull four wires out simultaneously, that's four circuits to keep track of for relocation. Being interrupted and subsequently losing track of what you've done can waste hours of work at that point.

[BlackBettyLimo]

How much work was it to install that harness? It can be much tougher to chase mistakes than to begin again...

If you're going to chase down errors I'd recommend starting with the ecm pinout and checking each wire one at a time. Mark down good/bad/notes on a separate notepad and if necessary only do a few circuits each night. I would probably divide the job into "check and report" and "repair" tasks to get a good idea of just how much work is to be done. If four wires are in wrong locations and you pull four wires out simultaneously, that's four circuits to keep track of for relocation. Being interrupted and subsequently losing track of what you've done can waste hours of work at that point.

Agreed, I probably wasn't clear in my post above but I'm starting over with the harness. I think it's time better spent. There's too many weird issues to chase down with the existing one.

At least the car does "run" now, despite some codes. So I'll just build the new harness on the side and take my time. It should be easy to swap it out when I'm done.

[lionelhutz]

What wiring diagram are you following? Not all applications have all the wires you list as missing and some won't be required in your application anyways.

You'll probably do a better job. Not sure who you used, but it sounds like he did a hack job on both the programming and the harness re-working.

The AC could be done. I'm not sure if the pressure sensor is absolutely required or not, but you'd need it feeding the PCM to have full control over the AC. Having the clutch control and pressure sensor means the PCM will properly control electric fans as the AC needs them. You may be able to turn-off the requirement for the sensor or just use a resistor instead and have it work.

[BlackBettyLimo]

What wiring diagram are you following? Not all applications have all the wires you list as missing and some won't be required in your application anyways.

You'll probably do a better job. Not sure who you used, but it sounds like he did a hack job on both the programming and the harness re-working.

The AC could be done. I'm not sure if the pressure sensor is absolutely required or not, but you'd need it feeding the PCM to have full control over the AC. Having the clutch control and pressure sensor means the PCM will properly control electric fans as the AC needs them. You may be able to turn-off the requirement for the sensor or just use a resistor instead and have it work.

For the new harness I was going to use this as a basic guide: http://lt1swap.com, as well as use the Painless Wiring LT1 harness installation manual, attached. If you've go any other useful schematics I'd love to know about them.

The goal is to keep the engine as stock as possible, so the deletions would be kept a a minimum. I'd like to keep all the emissions installed and working properly. I think I'll need a Park/ Neutral switch for that, as from what I've read it effects EGR operation.

I'll need to dig into the Caddy A/C wiring schematics to see what kind of signal it outputs and if the Roadmaster's PCM can accept it/ understand it.

Right now both fans are always on when the car is running even when the engine is cold (but not when ignition is in the key-on position). So I don't know if that's a PCM issue related to A/C, a perimeter not set correctly in the flash, or more bad wiring.

[kur4o]

The fans are on because egr valve is disconnected, the way i see it from your previous post.

http://www.gearhead-efi.com/Fuel-Injection/showthread.php?335-16188051-and-16181333-PCM-Information-EE-EEB

You can check this link for schematics.

I have the pinout for all the pins, even the unused ones, so if you have doubt for any pin or how is connected will try to help.
Do you have the vin for the caddy or model year engine, to check the ac wires and see if it can be reworked.

PNP switch is related with IAC valve operation, so if not connected expect to have some rough idle conditions. You need to ground the wire pin c15 to activate the switch.

[BlackBettyLimo]

The fans are on because egr valve is disconnected, the way i see it from your previous post.

http://www.gearhead-efi.com/Fuel-Injection/showthread.php?335-16188051-and-16181333-PCM-Information-EE-EEB

You can check this link for schematics.

I have the pinout for all the pins, even the unused ones, so if you have doubt for any pin or how is connected will try to help.
Do you have the vin for the caddy or model year engine, to check the ac wires and see if it can be reworked.

Thanks for the link. I also just bought the full service manual set for a '94 RM. Up to this point I only had the '95 supplement to work from. A lot was ok, some was not.

I have the full service manual for the Caddy so I'll scan and post the A/C pages when I get back to the car.

It's a 1985 Fleetwood Brougham and had a HT-4100 engine.

[BlackBettyLimo]

The fans are on because egr valve is disconnected, the way i see it from your previous post.

PNP switch is related with IAC valve operation, so if not connected expect to have some rough idle conditions. You need to ground the wire pin c15 to activate the switch.

I thought I had EGR related parameters turned off in the bin, but it's possible I didn't do it correctly.

Here's also what Painless says about the PNP circuit.
9681
9682

[lionelhutz]

On my engine the fans run when there is a DTC and CEL. I would expect yours is the same.

[BlackBettyLimo]

On my engine the fans run when there is a DTC and CEL. I would expect yours is the same.

Yeah I thought the fans would revert back to normal operation once I turned off all the offending codes in the bin, but either it doesn't work like that, or I'm missing something.

[BlackBettyLimo]

Update: I got dragged in to a major work hole the last few weeks but managed to finally spend a weekend on the limo.

Since it's been determined that my existing engine harness is to be scrapped, I bought what I was told was a used OEM '94 replacement.

9763

Last weekend I started cleaning it up and tearing it apart, and tagging all the plugs, etc

9764

The problem came when I was checking out the PCM connectors and noticed a few wires that weren't listed in the Service manual.

Red PCM connector cavity one has yellow wire. This runs to a three wire connector. One of the other wires is listed as Distributor Reference Low Signal.

9765

While we were trying to figure this out we noticed that the split plug for the coil were not present. They look like this on my current harness

97669767

On the new harness the Blue PCM connector has two knock sensor signal wires on separate circuits one in cavity 22, and the other in cavity 21(which is not listed in the service manual).
The existing has the two knock seasons on a "Y" connection.

Also, Blk connector cavity 22 is empty. According to the service manual this should be a tan/wht wire for the TCC temp switch signal.

Based on the above, can anyone tell me what year this harness is actually from? The omission of the coil wires seems to be an indicator, no?

Thanks,
Cory

[BlackBettyLimo]

I'm still trying to identify some of these

9768
ABS, right?

9769977097719772977397749775

[dave w]

I would use an ohm meter to see if any of the unidentified connectors go to the PCM, and figure out what the connector does based on the pin location at the PCM. I think you will find most of the unidentified connectors do not go to the PCM, and are "Chassis" wires. One method I use to quickly figure out if a connector goes to the PCM is slide the ohm meter (set to diode beep sound) leads across PCM pins. If I hear a beep sound I know the connector is wired to the PCM.

dave w

[ScottP]

Cory,

What you have there is a '96 B-body harness. The dead giveaways are:

1 - The 3-pin Metripack 150 connector you have labeled as Dist Low is the crankshaft position sensor.
This was only found on '96 B-body harnesses and was used for misfire detection. The 94-5 B-body LT1
harnesses did not have this.

2 - You have two separate knock sensor inputs on Blue 21 and 22. This too was unique to '96. The knock
sensors come in on two separate pins in '96 to comply with the OBD2 requirements for fault detection.

3 - The ignition coil connector on your new harness doesn't match the 2-piece version you show above.
Again, this was a model year 96 change for the B-bodies. The '96 LT1s used a new ignition coil with a
3-pin Metripack 150 series connector. This coil is also commonly found on the Vortec L30 and L31 engines.

In IMG_7655, the long connector with the stainless latch and big rubber boot on it is indeed the ABS module connector.

In IMG_7669, from left to right you have the ABS module ground, (4) PCM connectors, washer fluid level, MAF connector and washer fluid pump

IMG_7674 and 7675 are the wiper motor connectors

IMG_7681 is one of the front wheel ABS sensors

IMG_7687 The unlabeled 3-pin connector is for the ignition coil, and the one with the orange and black wires is the power steering pressure switch. The red and black wires are part of the AIR system.

IMG_7690 is the ignition coil connector

IMG_7691 show the 4L60E transmission connector (the big one), the VSS connector (violet and yellow wires) and one of the rear O2 sensor connectors.

Good luck with your repair.

-Scott

[lionelhutz]

#1 looks like ABS
#5 is not EFI related. It might be an ABS pressure sensor?
#8 looks like an O2 sensor connector.

Strip the harness enough you can figure out where the connector wires go. Label each connector and figure out where the wires go.

Most of the wires that don't go between a connector and the PCM are not required. You will have wires that come from the PCM connectors and don't go to another connector for a sensor. You may also find some sensor/solenoid/etc connectors with wires that go to the PCM except for 1 or 2 wires. You have to sort those wires out and figure out where they have to go. Mostly, I would expect these to be power or ground wires.

You have a full harness so you have gauge sensor wires, ABS wires, possibly heater wires or windshield washer wires etc in there. Once identified, you should start removing those wires and connectors. For example, take the main ABS connector and pull the wires out any place they go to another connector. Any of that wiring can be removed. I would pull the extra wiring out as much as possible in one piece and then chop off any extra wires still attached into the "good" harness leaving them long on the "good" side of the harness. If you then determine they aren't needed you remove them completely too. In other words, first pass is just to pull out any blatantly wrong wiring and connectors and eliminate as much obvious extra as possible. Second pass start sorting out what is left and remove what still isn't needed. The the third pass should get you close to a harness you can start to bundle back up and use.

[BlackBettyLimo]

Thanks dave w, ScottP and lionelhutz for the great info and suggestions.

Agreed that a tone/ beep Ohm meter is very very handy. I've been using one to find the plugs that I have identified to-date, and to diagnose the issues with the old harness.

Thanks for the identification of the remainder of the plugs. I was pretty embarrassed that it took me 6 hours of clean up and chasing wires before I noticed this harness didn't have the right coil wires. I've got to stop the blind assumption that everything I buy is going to be correct. By the end of this project I may know thing or two about an LT1 swap, haha just in time.

I called the guy who sold me the harness and he was pretty embarrassed that he had misidentified it for sale and he's willing to take it back. So I've got that going for me which is nice.

But this puts me at a crossroads with the million dollar question: Do I try to convert this '96 harness back to a '94, or, do I try to hunt down a used '94 harness and start over?

This one only cost me $100 and most other used ones are $200+, and my project funds are evaporating fast.

It seems I would only need to pull the coil circuit off the existing harness and swap it out on the '96 one. Except for the knock sensor circuit I have yet to research how much more of a pain it would be to modify it to work.

I'm off to the limo tomorrow to stare at it for a few hours and try to wrap my head around it.

[ScottP]

The '96 harness can be converted to '94 fairly easily, and the differences between them are fairly minor.
Some of the notable ones include:

'96 adds the crank position sensor and CCP flow switch (these go to pins that are not used on the 94-5's 16188051 PCM)
'96 has two separate knock sensors that come into the 16214399 PCM on Blue 21 and 22, where the '94-5 harness brings
both knock sensors in parallel on Blue 22 only.
'96 changes the ignition coil connector

These minor differences are what allowed '96 owners (like myself, quite a few years ago) to swap out the '96 16214399 PCM
for the 16188051 back when OBD2 flash/tuning tools weren't available. My 96 PCM went right back in once TC released his OBD2
package many years back.

I think the bigger issue with the harness you bought is that the entire underhood relay and fuse center was cut off. That means
you will need to extract it from the harness you're using now to make it "whole" again.

You may want to keep debugging what you've got - seems like you might be close? To that end, here's some
tests you can run to try to eliminate your DTC43.

First, inspect the Blue PCM connector - is there a dark blue wire in pin 22? There should be - that's the connection
to the knock sensors.

Next, using a DVM set to ohms, measure the resistance from the dark blue wire on pin 22 to engine ground. It should
measure ~1.95kohms. Each of the '94-95 knock sensors on a Bbody LT1 are nominally 3.9kohms each. In parallel, they
should measure 1.95k. If you get a substantially different reading than this, its the cause of DTC43 and is also why
your fans are running.

I bet with just a bit more guidance, you'll have things running well!

-Scott

[ScottP]

One more tip I just dug out of the mental archives.

Bbodies used two knock sensors in parallel on Blue 22 from 94-5, while Fbodies only used one.
This means that the test criteria for DTC43 is different depending upon whether you start with
an Fbody calibration or a Bbody calibration. If the tests I outlined above don't reveal any
problem, its possible that you have an Fbody calibration. A very easy way to test this would
be to unplug one of the two knock sensors and see if DTC43 goes away.

-Scott

[BlackBettyLimo]

One more tip I just dug out of the mental archives.

Bbodies used two knock sensors in parallel on Blue 22 from 94-5, while Fbodies only used one.
This means that the test criteria for DTC43 is different depending upon whether you start with
an Fbody calibration or a Bbody calibration. If the tests I outlined above don't reveal any
problem, its possible that you have an Fbody calibration. A very easy way to test this would
be to unplug one of the two knock sensors and see if DTC43 goes away.

-Scott

Thanks Scott, very helpful.

The existing harness I have has a broken Blue PCM plug, which someone prior has epoxied shut. They managed to put the knock sensor pin in the wrong location before doing this. So if I continue with the harness I have and want to make the knock sensors work again I'd have to address that.

Based on all of the above it may be worth the extra effort to just convert this harness. I'm headed out to the car now to check it out. Thanks again

[BlackBettyLimo]

Took the plunge and started the conversion of the '96 harness. Thanks to the help I was able identify and remove quite a few component plugs/ wires (ABS, wiper, washer, Low Dist, etc, etc). I'll pin out the rest of the harness and tag the remaining wires tomorrow. It may be a week before I can get back to the car and graft portions of the existing harness into the '96, but at least I'm headed in the right direction.

[BlackBettyLimo]

Hey guys,

My buddy and I have made some really good progress on the harness the last 2-3 days. It's almost fully installed and we are finishing taping it all up. I forgot to take a pic but it looks nice and clean/ factory now.

The good news is that the cars starts right up and "runs". The MIL light no longer stays on and the fans operate normally. The primary fan stays off until about 185º, then kicks in. The 2nd fan didn't kick on during our short idle (no road test yet)

The bad news is I didn'tt have my laptop with me and I was still running the old bin file supplied earlier (with EGR and CCR off, etc). We began to notice that the car was now having hard time idling and we are hearing pinging. Almost as though it was running lean? Honestly not sure why. Since everything is "turned off" in the bin it should run like it did before, no? Unfortunately I didn't have a computer to check out the data stream.

At this point what I'd like to do is upload a modified version of the attached bin file. I think the hearse bin is ultimately the best match for my setup. The only issue is I don't know how to change the tire height and rear gear ratio using Tuner Pro.

Kur4o - Any chance you can list the steps , or PM me, so I can learn how it's done (I'm also using the EEX file you gave me)?
Or if that's not a reasonable ask, could you please help and adjust this bin?

I'm headed out to the car tomorrow morning, so hopefully I'll be able to upload a new file and see if that clears up the way it's running. I'll do some logging and post results.

Here are the current changes I've made to the heres bin so far:

11/20/2015 19:36:55 Flag: * AIR Pump Enable changed from Set to Not Set..
11/20/2015 19:39:54 Flag: * VATS Enable changed from Set to Not Set..
11/20/2015 19:41:32 Flag: Vss Signal Diagnostic (Error 97) changed from Set to Not Set..
11/20/2015 19:41:50 Flag: VATS Diagnostic (Error 46) changed from Set to Not Set..
11/20/2015 19:42:00 Flag: Traction Control Diagnostic (Error 74) changed from Set to Not Set..
11/20/2015 19:43:41 Flag: * Air Pump Diagnostic (Error 29) changed from Set to Not Set..

Unless I've overlooked something everything else is "on". Rear gear should be 3.42 and tires are 28 inch (235/75R15).

Thanks!
Cory

[BlackBettyLimo]

Well, today was bit challenging. Since I haven't figured out how to adjust the Hearse bin, I thought I would just tweak the existing file and turn on EGR and CCP, etc. After making the changes and uploading the file, the car was still pinging and running like crap in closed loop mode (open loop seemed fine). I began to doubt my harness modification skills a bit.

I was monitoring using 9495 and as I started to try to wrap my head around the data stream I began to smell fresh gas. Lots of it. I looked under the middle of the limo and saw a 2 foot puddle of gas forming. After turning off the car and mopping up the mess I found that the metal hardline fuel line does not run the full length of the vehicle. A 4" piece of fuel hose joins the two sections of hardline at the midway point, and it had finally let loose. The upside is that we weren't road testing the car or even worse out for a night on the town the it happened.

Once that was fixed we got back to detective work. We notice that one of the O2 sensors was registering a very low voltage (0.03x) and the fuel corrections were not taking effect. We then got a DTC 46(?) which was the right bank O2 lean condition. At first we thought it could have been a bad O2 sensor or faulty injector, but the car was running well before the harness swap so it seems unlikely.

We started to pin out the circuit/ PCM plug and quickly realized that we had mislabeled the O2 connector on the harness. We had the left bank connector plugged into the right O2, etc. That's a good way to piss off a PCM. It was trying to make fuel corrections but the opposite O2 was seeing the adjustment.

Since we had already carefully routed the harness with zip ties and clamps, we just popped the pins in the connector and switched the positions.

We fired it back up and it ran normally, or so I thought. I was just going through he bin file and it looks like I forgot to correct some changes to the EGR Enable scalar (maxed out) I made when I was trying to bypass it. So the EGR probably wasn't working properly today.

Here are a few data logs (https://www.dropbox.com/sh/u2f79mbv435aj0m/AACrFSqcszF0ErsfrP67og5va?dl=0). I was getting 2 DTC codes for oil level and oil life. I just found them in a "Corvette Only" folder in Tuner Pro and turned them off.

Tomorrow I'll upload this final file and do a few more logs.

Here's a pic of our relay panel. We're still cleaning up the wiring and fabricating a bracket for the PCM.
9812

[1project2many]

I have to applaud your perseverance in this. It's unfortunate that you are having so many problems but I'm sure you'll get it figured out.


We had the left bank connector plugged into the right O2, etc. That's a good way to piss off a PCM. It was trying to make fuel corrections but the opposite O2 was seeing the adjustment.

Years ago I had to diagnose a trade in Corvette that had been deliberately connected like this. Inevitably one bank would be driven rich while the other was driven lean. I have no idea what magic the vehicle owner thought this change would produce but it ended up running horribly. Once the correct sensor was providing feedback the car ran well.

[lionelhutz]

Sounds like you're getting there. One thing to note is do not ground the PCM. Make sure your bracket is insulated or plastic.

[BlackBettyLimo]

Sounds like you're getting there. One thing to note is do not ground the PCM. Make sure your bracket is insulated or plastic.

Oh hell. I guess the aluminum bracket we spent the day fabbing up will have go :mad1:

Thanks for the heads up!

[BlackBettyLimo]

I have to applaud your perseverance in this.

Haha, I'm so deep in. The only way out, is through.

[Terminal_Crazy]

Sounds like you're getting there. One thing to note is do not ground the PCM. Make sure your bracket is insulated or plastic.Out of curiosity.. why ? noise?Presumably the PCM case is connected to a ground connection through the plug connectors.Mitch

[BlackBettyLimo]

Today was better than the last two combined. I uploaded the final tweaked bin file (EGR scalar corrected, and oil life/ level turned off) and the limo is running pretty smoothly now, and I'm not seeing any DTC codes.

We were screwing around with the PNP wire and as mentioned by a few of you guys in prior posts, it mainly has to do with the IAC circuit. Without the PNP grounded the idle RMP hunts from 630 to 670, and IAC values are 0. When you ground PNP the IAC value slowly increases to around 19-21 and the idle picks up to 700-715. It hunts a bit less with PNP grounded. Unfortunately my steering column only has a mechanical neutral safety switch, so there's no signal for me to hijack. My 4L60E does not have an external neutral switch as later years added, however the casing does have the mounting bosses for it. So perhaps i could buy a neutral switch and wire up a work around. They are only $40. If anyone has any experience/ feedback if that's a wild goose chase please let me know.

We were feeling pretty brave and decided to go on a road test and fill up the tank. Thankfully she ran smoothly and without incident. All shifts felt clean and the engine sounded happy. I'll probably run this bin for the time being. I was comparing transmission shift values with the hearse bin and they have higher thresholds, so it may be worth giving that a go and see how the ride characteristics change for driver and passenger. I think slower/ longer responses to driver input might be better if we've got drinks in hand in the back.

We got back to garage with some fresh optimism and started to dive in to the Caddy's ECM connectors. We found most of the dashboard indicators and were able to pair them with the LT1's PCM. Service Engine Soon (MIL), Service Now Stop Engine Temp (Cylinder temp sensor), Stop Engine Oil Pressure (added a sensor, operates outside of PCM)

Remaining punch list items:

I just realized the TCC Temp Switch is not hooked up, that got buried on a punch list somewhere. How critical is this?

PNP wire, as discussed. May just leave circuit open for now.

I've been running without the "home base" air intake plenum. Any idea if the the car run louder or softer if I put it back on? There isn't room for the other resonating baffle after the air box.

Need to hook up the No Charge Indicator light on dash, although I'm running a single wire alternator now. Not sure how to attack that yet.

Getting closer!

[BlackBettyLimo]

Maybe a variation for this for the PNP circuit. i've seen some threads referencing a diode, but have yet to understand the need or application.


9828

[lionelhutz]

Not grounding the PCM is to eliminate ground loops. The PCM is grounded through the harness connectors and typically the wires go to the engine where it needs to be grounded. A number of people have fried their PCM by grounding it to the body and then having it complete the ground connection from engine to body. The GM holders are always plastic for good reasons.

I think there are different idle rpm target tables for park and for in gear. I'd have to fire-up my tablet to take a look and confirm. If you find them, make the lower table the same as the higher rpm table and then it should idle the same regardless of the P/N wire connection. I never bothered with the switch. Mine runs pretty good without it and I just can't be bothering making something up to wire it. I haven't heard of any good reason it needs it. Your relay idea looks good but then it just adds another possible component that cause a no-start when it fails.

I'm not sure what TCC temp switch you're looking at. There is a temperature sensor inside the transmission but it's wiring is part of the harness to the transmission connector and you should have got it if you kept the transmission harness.

I don't know what a "home base" air intake is.

The 1-wire alternator should still have the light terminal you can connect a charging light to.

[BlackBettyLimo]

Not grounding the PCM is to eliminate ground loops. The PCM is grounded through the harness connectors and typically the wires go to the engine where it needs to be grounded. A number of people have fried their PCM by grounding it to the body and then having it complete the ground connection from engine to body. The GM holders are always plastic for good reasons.

I think there are different idle rpm target tables for park and for in gear. I'd have to fire-up my tablet to take a look and confirm. If you find them, make the lower table the same as the higher rpm table and then it should idle the same regardless of the P/N wire connection. I never bothered with the switch. Mine runs pretty good without it and I just can't be bothering making something up to wire it. I haven't heard of any good reason it needs it. Your relay idea looks good but then it just adds another possible component that cause a no-start when it fails.

I'm not sure what TCC temp switch you're looking at. There is a temperature sensor inside the transmission but it's wiring is part of the harness to the transmission connector and you should have got it if you kept the transmission harness.

I don't know what a "home base" air intake is.

The 1-wire alternator should still have the light terminal you can connect a charging light to.


Haha based on a few LT1 forums, "home base" (aka "home plate") was the way people were describing the top air cleaner which looks like a home plate from a baseball diamond. I wasn't sure if it acted more like a sound baffle (eliminating drone at certain frequencies?) or just tuned the general tone of the engine.

hmm, I thought I had stubbed a wire out that was labeled TCC temp, that was outside of the Trans plug. I'll double check.

I'll also check out the Alt and see where the light terminal might be hiding.

Thanks for the insight on the PCM loop grounding. Right now the PCM is mounted in an aluminum mount, however, that is affixed to the top side of the plastic wheel well of the Caddy so it's actually 100% insulated from ground loops. Maybe I'll rover the thing in electric tape just to be safe.

I'll dig around and look for the PNP table your referring to. I think my brain is finally beginning to understand TunerPro a bit. Emphasis on "a bit".

I really appreciate the time you've taken to help throughout this project! Thank you! :thumbsup:

[BlackBettyLimo]

I can't believe it's been six years since I started this LT1 swap thread! I just re-read the entire thing a few days ago and honestly it was like reading a foreign language, I had completely forgotten everything. I just brought myself back up on to speed on $EE, BIN, XDF, ADX, Datalogging, Scan1995, WinFlash, TunerPro. This thread was so helpful, both then and now, so thanks again for taking the time to help with this project. During my refresher course I found the latest EEX definition file and the latest V5 of TunerPro, so great to see the development continue! I'll be sure to make some donations shortly.

Overall, the limo has been running well. Last year we took the plunge and got some new paint/ carpet/ interior, and I finally got the AC working just in time for winter. I'll need to update the BIN for that at some point, I think we turned all of the AC related diagnostic stuff off.

Punch list wise, I think I may need to install a power steering pressure switch (doesn't exist on original Cadillac system) to let the ECU adjust RMP when under load. The car will die every now and then during a tight low-speed cornering event. I also need to get the OEM Air Pump back on, get a VSS to mechanical cable converter box installed so the dash speedo can work again, replacing some leaky trans lines, and sort out some door lock issues.

Other than that she's a runner!

Here's some updated pics:

17330

17331

17332

[BlackBettyLimo]

Oh btw, during my deep dive I came across a EE Speedo Calculator.xls from EagleMark. Now I might be getting a bit out of my league here, but I noticed that the formula for Speed Scalar - Divisor in the .xls ((PPM + Speedo Scalar-Base)/4000) differs from what the rollover "tool tip" in Tuner Pro says (4000/ (PPM + Speedo Scalar-Base)). Just wondering if the tool tip in Tuner Pro is a typo/ flipped?

There is also a very small discrepancy in the labeling between TP and the xls, which for a slow-on-the-draw guy like me found a bit confusing. The xls refers to "Scan Tool Scalar" and TunerPro calls it "Speedometer Scalar - Scan Tool". Seems like it should be obvious, but I'm thick. So, I've re-formatted it a bit for newbies like me and also added (hopefully accurately) a Tire Size to Revolution Per Mile calculation in there.

Here's the formula I used: ((Tire Section x Aspect Ratio (in %) x 2) / 25.4 (mm --> in conversion #) + Wheel Size (R)) x 3.1416 (Pi) = Tire Circum in inches/ 12 = Ft/ 5280 = Revs per Mile

Does anyone know how to upload an.xls file? I only see options for pics and video

Here's a temporary Dropbox link if you want to check it out: https://www.dropbox.com/scl/fi/moe8pg7btxwyk9npls5ra/EE-Speedometer-CalculatorV2.xlsx?dl=0&rlkey=i505ljiudvlfdoxbmbba02q30

Am I correct in understanding that the three Speedometer Scalars (Base, Divisor, Scalar Tool) are only values you need to change when dealing with Rear End Ratio and Tires Size?

[1project2many]

Nice to see you're still around.


Overall, the limo has been running well. Last year we took the plunge and got some new paint/ carpet/ interior, and I finally got the AC working just in time for winter.
The limo looks great. The seats look very comfortable.


Just wondering if the tool tip in Tuner Pro is a typo/ flipped?
I *believe" the rollover tip is correct. Open the XDF and look at the formula to confirm.


((Tire Section x Aspect Ratio (in %) x 2) / 25.4 (mm --> in conversion #) + Wheel Size (R)) x 3.1416 (Pi) = Tire Circum in inches/ 12 = Ft/ 5280 = Revs per Mile

This formula calculates feet/rev/mile or miles travelled per rev.
29.5" dia # pi = 92.676905 in / 12 / 5280 = 0.00146270.

You need to invert the result to get rev/mile:
1/.00146270 = 683.66

The challenge with using completely calculated values is that the unloaded tire circumference does not match the loaded (or rolling) tire circumference. For the same 92.5" circumference tire the actual rolling circumference requires 708 revs/mile.
https://www.goodyear.com/en-US/tires/wrangler-sr-a/sizes-specs



Am I correct in understanding that the three Speedometer Scalars (Base, Divisor, Scalar Tool) are only values you need to change when dealing with Rear End Ratio and Tires Size?
That's all I change.



Does anyone know how to upload an.xls file? I only see options for pics and video


Hmm... what are you seeing? Feel free to contact me off-list to keep this thread clean.

From the "Attachments" section of a post reply page:
Valid file extensions: adl ads adx bin bmp cal ctz doc ds ecu efi gif hpt jpe jpeg jpg ods pdf png psd src tun txt uni wav xdf xdl xls zip

[BlackBettyLimo]

I *believe" the rollover tip is correct. Open the XDF and look at the formula to confirm..

Screenshot shows 4000/ X vs X/4000
17338




The challenge with using completely calculated values is that the unloaded tire circumference does not match the loaded (or rolling) tire circumference. For the same 92.5" circumference tire the actual rolling circumference requires 708 revs/mile.
https://www.goodyear.com/en-US/tires/wrangler-sr-a/sizes-specs.

Ohhh I hadn't thought about load as an influence, thanks for the clarification.




That's all I change.

Great, thanks





From the "Attachments" section of a post reply page:
Valid file extensions: adl ads adx bin bmp cal ctz doc ds ecu efi gif hpt jpe jpeg jpg ods pdf png psd src tun txt uni wav xdf xdl xls zip

-forehead smack- I was using Quick Reply instead of Go Advanced. I told you I forgot everything...

[BlackBettyLimo]

Formula wise it seems like we are coming to the same conclusion whether it’s by Tire Size or Diameter the results basically the same, despite the fraction rounding difference. I updated the .xls to V3 which has both calculations. Attached.

I used your Goodyear link (https://www.goodyear.com/en-US/tires...-a/sizes-specs) and ran a few of their tires though both calculators, not only make sure they were giving the same calculated results, but to compare and contrast Goodyear’s listed rev per mile number vs our calculated one.

Here are value differences between the published Goodyear rev per mile value, minus the calculated one (always a lower number):

245/75R16 = +24 (i.e add this number to the calculated value to meet the manufacture's published rev per mile)
225/70R15 = +26
265/60R18 = +21
275/60R20 = +23
275/55R20 = +23

It looks like the average adjustment needed to be applied to the calculated value is +/- 23 rev per mile, so I added a "Rev per Mile Adjustment Value" cell to the spreadsheet and tested everything using a Goodyear 275/65/R18 (32.1 Dia, Revs Per Miles = 651).

The calculated result is now 651.x, within 1 revolution per mile rounding error.

Not too terrible?

[steveo]

one problem with the speedo correction is that, if you're using an electronic transmission, a lot of transmission shift points are vehicle speed based
since the vehicle speed is taken from the trans it will shift perfectly until you correct the speedo, then it'll shift in odd places
so you have to scale all those too

[BlackBettyLimo]

one problem with the speedo correction is that, if you're using an electronic transmission, a lot of transmission shift points are vehicle speed based
since the vehicle speed is taken from the trans it will shift perfectly until you correct the speedo, then it'll shift in odd places
so you have to scale all those too

Hey Steveo,

Thanks for the quick reply

The limo is shifting pretty well overall, sometimes there's an abrupt 1-2 shift (depending on rate of accelerator input), but usually it's pretty darn smooth. I'll have to interrogate the ECU and pull the existing BIN to see if there were any mods made. We might have used a BIN for a hearse (EE_16200281 1994 D Hearse Auto 2.93.bin) as our base since that felt like they could be similar rolling weights. I can't remember if one off you fellas massaged that data or not when you were helping me ago long ago, but as I'm typing this... obviously that BIN is calibrated for a 2.93 rear end vs the 3.42 we have, so it would take sense if there was an adjustment.

Out of curiosity are there multiple scalars to adjust? I'll dig around a bit tonight and take a look at TunerPro. I should be getting out to the limo in a few days to grab the current BIN.

[steveo]

i think anything in the transmission tables that has a value in mph is worth taking a peek at