7427 install, first impressions

[EagleMark]

What's a thottle kicker?

there's a varity of codes depending on vin "?" here's one for a 92 93 chevy 5.7L Vin J
36 ECM detected less than 60 high resolution timing pulses between each low resolution pulse for 5 consecutive cycles.

other 36 codes could be MAF or DIS on a quad 4 engine.

What was your PCM out of?

[dave w]

Yes, the old esc will be completely removed from the system once I get some time. I plan on doing that when I do the ecm plug swap and get rid of my adapter harness I am using right now.
The local parts stores done have that brand of knock sensor, is there a way to cross refrence that to another brand? The monkey behind the parts counter had no luck doing so.

Maybe this information will help? Bring an Ohm meter to make sure the knock sensor is 4K.

dave w

[JeepsAndGuns]

What's a thottle kicker?

there's a varity of codes depending on vin "?" here's one for a 92 93 chevy 5.7L Vin J
36 ECM detected less than 60 high resolution timing pulses between each low resolution pulse for 5 consecutive cycles.

other 36 codes could be MAF or DIS on a quad 4 engine.

What was your PCM out of?

The PCM itself is from a 95 half ton truck, 350 automatic. BCC, BJYK was the chip that was in it. Right now I am using the moates G1 adapter and running a 27SF512 chip. The bin I am using is one posted up here on my last post. BMHK, witch is supposed to be for a 454 with a manual trans. It of corse uses the 0E (tunerpro V5) defination. I am also using the (tp V5) 0E datastream defination for the datalogging. Its what labels the code 36 as "throttle kicker failure" Also when looking through the bin, there are paramiters for the "throttle kicker" So, did some trucks actually use a "throttle kicker"? From what I have seen online, a throttle kicker is simply a solenoid or stepper motor that pushes aganst the throttle to open it slightly, in order to raise the idle.
It seems to run fine, well better than fine, like mentioned at the start, it runs way better than it did with the 7747, so I'm not really wanting to think its those other trouble codes (I saw those too when searching)

[EagleMark]

I don't know the answers, but I'll bet the throttle kicker has something to do with the manual trans and shifting, so between shifts the engine does not go back to idle, cleaning up emmisions and making shifting easier.

EDIT: Found three for 1995

DTC - 36 MAF sensor error

DTC - 36 24x Crankshaft position sensor circuit error

DTC - 36 4T60-E Shifting Error

Full list found here:
viewtopic.php?f=9&t=311

[JeepsAndGuns]

Yea I found those same codes with google, they didnt really seem to fit since I dont have a maf sensor, or a 24x crank wheel. But whats that 4T60-E shifting error? Something to do with the auto trans?
I looked last night, and both tuner pro version 5 0E and 0D definations and adx files say 36 is throttle kicker failure. And both have paramiters in the bin for a throttle kicker. So is it possiable they have been miss labeled by the person who made the definations?

I even went as far as calling the local chevy dealer and asked parts if there was a throttle kicker on any of the 95 model trucks. He had never even heard of a throttle kicker, and could find nothing of the sorts in his parts program. I then talked to one of the shop techs and he seemed to think mabey it was used on like the kodiak HD trucks that had a pto, as a way to run the engine at fast idle. I transfered back over to parts cause he said he could look up the BCC. All he could pull up was that it was a 5 speed bin, but had no info on what that BCC was originally supposed to be for. (this is the BMHK bcc, just fyi)
One thing I might try, is to load up the BJYK bin (350 auto) that I made up and see if the code sets when driving with that bin. Just depends if I have time this weekend.

[JeepsAndGuns]

Well I think I have figured out this throttle kicker issue, well sort of, if we really want to call it a issue.
I have noticed the last few times I have drove it, it wanted to stumble, kinda almost stall as I was pulling out from a dead stop. This was only while letting out on the clutch to pull out, if it was a rolling start, it wouldnt do it. I had to give it more throttle to pull out than I should. I thought this was odd as it didnt do it the first few times I drove it, even more so odd as the first few times I drove it, it actually pulled out better than it did with the old 7747. The issue seemed to appear as I was tuning my fuel maps. I was starting to think there was some issue with either fuel or spark starting to show itself.
As I was driving back home from a friends house, it hit me . Back when I first started getting that error code, I noticed once or twice, the code for iac failure was on too. I thought that was very odd, as the iac was working perfectly fine. So I just ignored that code. When it hit me, I realaized the pulling out issue started about the same time I turned off the error code for the throttle kicker failure. But thinking it was a external bolt on part that was not being used (like the egr valve), I went to paramiters for the throttle kicker and set the enable temp to max so it would never turn on (just lke I did the egr) And then turned off the error code for it.
So I figured, mabey this had something do do with the pulling out issue. So I went back into the bin, and set the enable temp back to what it was stock. I then test drove and the pulling out issue is gone. I watched my datalog dash while pulling out, and when you do so, it must sense from the engine load increasing and rpm dropping slightly, that you are trying to pull out, cause when I am pulling out, it openes the iac up a significant ammount, I guess thats the "kick" It opens it up to give you more throttle and air to give it a extra kittle kick when pulling out.

Only one last issue, I am still getting that iac failure error code. The check engine light is not on, but the error code is showing on the error code list in the data log. I find this very odd, as the iac is working perfectly fine. Could the error code simply be stored in the memory, and just show up now every time I drive it? I hear that you have to have these un plugged from power for several days to clear the memory, is that true? I went ahead and unplugged it and I am leaving it unplugged untill next weekend when I get some more time to do some more tuning.

[dave w]

Well I think I have figured out this throttle kicker issue, well sort of, if we really want to call it a issue.
Only one last issue, I am still getting that iac failure error code. The check engine light is not on, but the error code is showing on the error code list in the data log. I find this very odd, as the iac is working perfectly fine. Could the error code simply be stored in the memory, and just show up now every time I drive it? I hear that you have to have these un plugged from power for several days to clear the memory, is that true? I went ahead and unplugged it and I am leaving it unplugged untill next weekend when I get some more time to do some more tuning.

I usually need to adjust the IAC / Throttle minimum air to about 10 ~ 15 steps with the engine fully warmed up and parked in neutral. There are several methods to adjust the minimum air. My minimum air adjustment method is NOT the conventional method. I simply adjust the throttle stop screw, while watching the data log, with the engine running, fully warmed up and parked in neutral.

The memory will clear after 30 seconds or less after disconnecting the power from the PCM.

[EagleMark]

I do what dave w does, but when done TPS voltage should be under 1.0 volt. Optimum is .54. but told from pioneers on Thirdgen anything under 1.0 volt is fine.

What JeepsandGuns is saying about throttle kicker has been my suspicion the entire time that there is more in the chip different for manual than just turning off the auto trans. I was told this by a Detroit EFI engineer to always start with a manual bin for manual trans as there is differences in chip. But not apparent in anyones hacks, that I have seen so far.

Since there are 100 things in IAC logic it would be plausible. Since we know even before EFI that contraptions were made to slow throttle to idle when shifting on carburetors cars for EPA/Emissions reasons it would be silly to think they are not in EFI programming.

EDIT: Yes the error code will be stored even after the problem is fixed. There is a paremeter that clears error codes after so many starts and not receiving an error. Just disconect PCM or batterey, I always give one minute, I do not know actual time needed, but one minute always works on any I have done.

[EagleMark]

What did you do for the adapter? Just whack out the recieving plug from the 1227747?

[JeepsAndGuns]

Yep, I found someone with a fried 7747 and just de sodered the female plug from the main board, then sodered the wire directly to the pins. It was actually a roal pain in the ass to make, but I was just very intimadated by the pcm and I just wanted to be able to plug my old ecm back in and be able to drive it if the tuning process took a long time.
Ha, I never plugged the old 7747 back in once I plugged in the 7427.

I do have a couple questions about the wiring change over diagram. I saw no input for the crank signal (7747 pin C9), I didnt notice this when making the adapter, but when I swapped all the pins into the pcm plugs last night, I had that left over. I figure the pcm doesnt use this? If not I will just remove it from the harness.
Also, the 7747 had two power inputs, B1 and C16. But the 7427 only had one, I'm guessing the other one just gets removed?
And last, are the 7427 pins E14 and F14 inputs or outputs? The diagram shows both of those pins going to the old pin C14. But there is only 1 C14. So do I need to splice into the old C14 wire and add another wire so I can hook one to E14 and the other to F14? Thats what I did on the adapter, I just tied both together and connected it to pin C14

[Six_Shooter]

The '7427 does not use a crank signal input. Originally this would have been connected through the 3A "CNK" or "CRNK" fuse in the fuse panel.

The others I have to look at the at the wiring diagrams to remember before commenting.

[dave w]

I do have a couple questions about the wiring change over diagram. I saw no input for the crank signal (7747 pin C9), I didnt notice this when making the adapter, but when I swapped all the pins into the pcm plugs last night, I had that left over. I figure the pcm doesnt use this? If not I will just remove it from the harness.
Also, the 7747 had two power inputs, B1 and C16. But the 7427 only had one, I'm guessing the other one just gets removed?
And last, are the 7427 pins E14 and F14 inputs or outputs? The diagram shows both of those pins going to the old pin C14. But there is only 1 C14. So do I need to splice into the old C14 wire and add another wire so I can hook one to E14 and the other to F14? Thats what I did on the adapter, I just tied both together and connected it to pin C14

The below information is directly from the notes on Thridgen.org

Old C14 is a 5 Volt Reference and goes to New E14.
Old B1 Battery Volts - goes to New E16
Old C16 Battery Volts - goes to New E13 (Input in place of Brake Switch)

**F14 is not listed in the notes from Thridgen.org.
***1994 Wiring Schematic I have shows F14 as a TPS 5V Reference.
****On the '427 conversions I've done F14 is not wired, nothing going there, not needed for anything!

dave w

[EagleMark]

Taking notes as I build the 427 system for sons truck... yes I am procrastinating...

[attachment=0:pcy1jgip]427.jpg[/attachment:pcy1jgip]

[JeepsAndGuns]

The below information is directly from the notes on Thridgen.org

Old C14 is a 5 Volt Reference and goes to New E14.
Old B1 Battery Volts - goes to New E16
Old C16 Battery Volts - goes to New E13 (Input in place of Brake Switch)

**F14 is not listed in the notes from Thridgen.org.
***1994 Wiring Schematic I have shows F14 as a TPS 5V Reference.
****On the '427 conversions I've done F14 is not wired, nothing going there, not needed for anything!

dave w

I wasnt sure about the E14 and F14, thats why I wanted to check. Seems I remember on the 7747 system, the 5 volt refrence from the ecm goes out in the harness and then splits off and connects to the tps and map, where it appears on the original pcm harness, it must run them seperate.
I forgot to ask about that brake switch input (E13) I have had nothing connected to that pin the whole time I have been running my adapter. Everything has seemed to be ok. The diagram I have says its power when brakes are not applied, and no power when brakes are applied. So I guess its just been thinking I have had the brakes on all this time...lol

[EagleMark]

The brake wire your talking about, I beleive is for lockup converter. Hence no brakes means it has power to lockup, brakes applied and unlock. It is needed for 700R4 on 7747. IIRC. I don't see a need for it on a manual... unless the 427 does something differant.