Congrats on getting the caddy back on the road!
Congrats on getting the caddy back on the road!
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.adxOriginally Posted by kur4o
Last edited by jthompson122183; 10-18-2015 at 11:20 PM.
97z28 A4 obd1 swap(16188051)
Tunerpro Newbie
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!
Thanks of the file! Hopefully I'll be able to check it out before I leave town!
Thanks! As you'll read the fight isn't over just yet. But I'm closer than ever!
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.
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.
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.
The fans are on because egr valve is disconnected, the way i see it from your previous post.
http://www.gearhead-efi.com/Fuel-Inj...rmation-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.
Last edited by kur4o; 10-19-2015 at 10:44 PM.
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.
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.
Attachment 9681
Attachment 9682
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.
Last edited by BlackBettyLimo; 11-11-2015 at 04:36 AM.
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