1992 GP with 3100 installed

[mike1976]

Hello again everyone. I just put a 3100 V6 from a 1996 GP into my 1992 GP and shortly after I did so and after some fun driving, the check engine light came on. The codes it threw were 23: Manifold temperature too low, 33: MAP sensor circuit too high, and 43: ESC module or sensor problem. The engine runs very quiet and isnt loud and doesnt knock either. Can anyone help me figure out where to start with these codes so the check engine light dont come on anymore.

[60dgrzbelow0]

Belatedly... this very handy site will help to amplify information on Codes, 23,33 and 43 (as well as many others) and perhaps indicate a direction to look in to solve the mystery. So far ...the common denominator between all three of these code problems on their unique symptoms list seems to be a "Defective ECM":

http://www.gnttype.org/maint/malf.html

You don't say whether you swapped out your 1992 GP ECM for one matching your 1996 GP 3100 Engine (not certain that it is required...but other more informed mech-members here can chime in)

eBay Lisings for 1991-1993 GP ECMs:

http://shop.ebay.com/i.html?_nkw=1992+grand+prix+ecm+&_cqr=true&_nkwusc=1992+gran+prix+ecm&_rdc=1

eBay listings for 1996 GP ECMs:

http://shop.ebay.com/i.html?_nkw=1996+grand+prix+ecm&_sacat=0&_odkw=1992+grand+prix+ecm&_osacat=0&_trksid=p3286.c0.m270.l1313

[Azrael]

Check/clean your ground wires too. Poor grounds can skew sensor readings.

[pocket-rocket]

You don't say whether you swapped out your 1992 GP ECM for one matching your 1996 GP 3100 Engine (not certain that it is required...but other more informed mech-members here can chime in)

The 92 GP ECM should run a 3100 just fine, but for maximum benefits, it should be tuned due to engine differences (head flow, ect), but if untuned, it should still run just fine without concern.

[mike1976]

The ECM I have in the car is the original ECM that came stock. I never did replace it when I installed the 3100 motor in the car. I cleaned the grounds and connectors, and because some clips were broken on the wiring harness I replaced the whole harness as well for the engine. I had the codes cleared and then drove it, and the light came back on, and now its just 23: manifold temperature too low and 43: ESC module or sensor problem. The light also comes on when the car is stopped, the RPMS drop from 750RPM to 400RPM, the car doesnt die but acts like the timing just got cut back as it is sluggish until it is moving. Once moving the light turns off and passing cars is fine as there is no loss of power, just loss of power at idle. Anyone know what the little sensor is that is located on the air cleaner housing? Someone told me that could be the problem.

[pocket-rocket]

That would be the AIT, or Air Intake Temperature sensor. That and the MAP sensor is how the ECM determines how much air the engine is getting.