TGP ecm running 3.4dohc manual - pig rich , help

[Kohburn]

I currently have a 95 grand prix 3.4 dohc engine swapped into my 86 Fiero runnign on a 90 TGPecm .. the auto tranny has been disabled for using the manual trans in my car.. and I had someone burn a chip that was tweaked to help it run the 3.4..

currently it will barely idle and is running pig rich.. I hooked up my actron scantool and wrote down a few of the recorded data logs.


when engine OFF

Throttle % 1 - TPS volt .52
Throttle %100 - TPS volt 4.41
Spark Adv -4
MAT 69*
02S (mv) 4
MAP 1.59
MAF 0
INJ pw 15
IAC 105
ESC 21
exh RICH
A/F desired 11

running with foot on throttle keeping it from stalling

RPM 1625
TPS v 1.04
throttle % 16
spark advance -4
02S mv 852
exhaust RICH
MAT 72*
MAP v 1.22
MAF 49
integrator 128
INJ pw 4
IAC possition 118
ESC 2
A/F desired 10

after goosing it

RPM 6000
TPS v .52
throttle % 1
spark advance 0
02S mv 804
exhaust RICH
MAT 70*
MAP v 0.35
MAF 33
integrator 128
INJ pw 0
IAC possition 118
ESC 19
A/F desired 13
knock ret 0

not sure exactly what info to gather to help diagnose the running WAY rich

any advice you can offer would be great.

[SappySE107]

Are you running boost? If its MAF, why are you running TGP code? Im completely lost on what you are doing here. Those computer readings are all but worthless too. the desired A/F is making it rich, but it sounds like its too rich. Why not run a 94-95 DOHC ECM and tune the MAF with boost?

[Kohburn]

its running MAP setup not MAF - at the time I didn't know anybody was tuning the 94-95 dohc MAF to take boost -- I'm not currently putting any boost to it - just trying to get it to run right NA. Then I'll start adding boost to the mix.

I've been told that a 2 bar MAP should be reading about 2.45v with the engine off and key on but mine is reading more like a 3bar - may account for it running so rich

[SappySE107]

Your TPS is wrong too. I think you have a wiring issue with the 5 volt constant wire. Im not sure but I think it may be connected with TPS and the MAP. I know TPS and something else are combined and when its not, the TPS won't scale properly at all. The spark advance looks pretty off as well. -4 degrees, 0 while running.

[Kohburn]

well the 5volt ref wire Y's and goes to botht he map and the tps - the computer doesn't seem to think that there is a TPS issue because its what output the 1% and 100%

[SappySE107]

it should be at 0% though, not 1%.

[bszopi]

Wasn't mine ranging between 1-4% when we had the wires connected wrong? (ie, grounds mixed up)

[SappySE107]

Yup. Anything over .5 volt was registering a throttle position. It should be scaling it but its not.

[Kohburn]

Wasn't mine ranging between 1-4% when we had the wires connected wrong? (ie, grounds mixed up)

hmm hadn't thought of mixed grounds.. that may be a possability - I'll check with my meter later..

[Kohburn]

well can't tell if i have any grounds mixxed without pulling the harness out

but I did some more diagnostics and the MAP now reads 2.31 inside the car - the ESC and KR have settled down and the thing actually idles nice once it hits closed loop.. not perfect - still a bit rich - but I think the addition of a code 34 (low map voltage) may be the culprite

[TurboGTU]

On the ecm harness...pin C12 should be conencted to the map sensor and the TPS and the EGR (if electronic). C5 and C10 would go to map sensor, intake air temp sensor, coolant level/corrositity sensor, TPS and engine coolant temp sensor.

[Kohburn]

double checked my MAP voltage at the sensor last night an confirmed the 2.32v with engine off - guess that means the brand new special order MAP is bad

[TurboGTU]

You know that map voltage changes with altitude. So thats about right. But if you want to swap it...it won't hurt if it has warrenty. You haven't mentioned injectors..or if you have messed with the fuel rail by adding a FMU.

[SappySE107]

The stock injectors should work fairly decent with the TGP code. I don't know what the fuel tables look like in comparison though nor what was modified in that chip.

[Kohburn]

haven't messed with the fuel rail or injectors the engine is basicly stock right now

it doesn't run that bad once it warms up - but untill then it will not idle without help. I'll be pulling more data in closed loop tonight hopefully