My iroc just developed this problem. Whenever i go from park to reverse or drive it will stall out. This is a 305 TPI car. Today i got a trouble code 32 which is EGR but that trouble code went away once the car stalled. Could this be my EGR valve sticking open? Or is there something else i should be looking into? I can get it into gear without it stalling but it takes a good amount of patience and some gas while moving the gear shift to drive or reverse. Once its in gear and has not stalled imediately it wont stall.

 

Could be not enough timing
messed up TPS
messed up IAC

I doubt it's the EGR.

 

Ill check into both more carefully. Last night i went out to adjust the TPS and i didnt get any readings on my volt meter. I mean it read .001 or nothing so im assuming my TPS is fried. Im going to run with that for now and see if TPIhearse has a good one lying around.

 

yea that would mean the tps is bad... if u checked it right but if the tps was bad it would run like crap in park and neutral as well... it might be the IAC... i would take it out and clean it and clean the hell outa the TB.... i cant help but think that it could also be ur torque converter. it could be going... have u noticed any differences with the shifts and how the car drives.

the TPS should read .5-.6 at idle in park and 5v at max pedal. so u kno when u replace it and adjust it. also make sure the IAC is adjusted properly that the needle is out far enough if not get a manual and it will tell u how to adjust it.

 

Well TPIhearse did have a TPS and we put it on the engine and still no readings. Either there is something wrong with the signal getting to the TPS or i just ended up getting two fried TPS's. And the car runs shitty in park and neutral as well now. Its hard to start.

The IAC has been eliminated as the cause of the problem as well. We unplugged it and the idle picked up but putting it into gear still resulted in the car stalling.

The MAF is the next in my book. It seemed less like it wanted to stall when i unplugged the maf. I still got it to stall with it unplugged though.

 

how about lock up switch?

 

Ill ask my dealership about the lockup switch tomorrow. They are clueless as to what is going on with this car. They are getting frustrated as well as me. I gave up and gave it to them but they are having no more luck than i did. Here are the list of mods that i kno about on this car

Edelbrock headers
Flowmaster 3 inch exhaust
LT4 cam
Edelbrock lower intake
TPIS runners
Ported plenum
coolant bypass
descreened maf
Shift kit
Underdrive pullies
custom burned chip (not sure what was changed)

The shop has been all over this car. It is not throwing any codes. They thought it might be the computer but it wasnt. They checked the TPS and IAC and both checked out. Whats funny is if you give it gas and put it in gear its fine and runs good and will only ocationally stall out at stop signs. They have played with the timing and everything and been over the entire engine and are coming up empty. What are they missing? This isnt some crummy little backyard shop either this is a chevrolet dealership.

 

A fuel issue maybe? I know yours is a TPI, but my carbed LG4 did this same thing a while back. Turned out to be a bad float (I think), but it was just dumping unmetered fuel in there. Maybe you're having issues with your fuel pressure regulator?

 

That is funny that you say that cause when it went in for this problem the first time (this is the second time its been in for the same problem) they found that the adjustable regulator someone had put in was crap and screwing up my fuel pressure so they replaced it with a stock one so my fuel pressure is what it needs to be. Thanks for the reply though. I really want my car back .

 

i had this sorta problem on my winter car. spirit. anywho my throttle springs were stuck plus the butterfly in the tb was was really derty causing it to cut off fair when slowing, shift, any time i relased the pettal. maybe try and clean the tb butterflys and wd-40 the springs. could help? i actually have this same problem with my car, except it does not stall when shifting, but slowing, it drops to 400 rm, shakes and feels like its going to stall. then it kicks itself back up to 700 rpm and is fine. now i have to say, the chev delership isnt always a good place to go. had bad exprences where i live. there not to to smart.

 

thanks for the tip but i already cleaned the bejesus out of the TB cause it was dirty. Still didnt help. This chevy dealership seems pretty good so far except for this. Its got them stumped so i may just end up bringing it somewhere else if they cant solve it by the end of the week.

 

Could it be that since this engine is so modified that a stock FPR ( the one on it now) is not up to the task of delivering what this engine wants? Should i think about getting an adjustable FPR and seeing if that solves the problem? It had one before when i first got it and ran fine but then the AFPR went bad so the shop replaced it with a stock one.

 

bump..anyone...AFPR vs stock? I have stock on a very modified car. Could this be posing a problem?

 

yea man that sounds like a good point. if the car is running lean it will stall out right? its sorta ghost problem so you have to just try things. you will eventually fix it but for how much $

 

Unless there's a problem with your stock fpr, changing it to an afpr won't really help. All you can do with the afpr is add more fuel pressure with better atomization. Just change your chip programming if you think you're fuel starving.
Have you done a fuel pressure test yet? That'll help determine if a new regulator is in order.

 

yeah i also have that problem and on top of that it seems to get worse when it rains. it starts and then dies almost instantly. i have a AFPR in but it s set almost stock right now or so i think it is. what it s supposed to be set at. and any other ideas?

 

You may have a short in one of your plug wires or somewhere in your dizzy.

Stock fp is 43 static.

 

Im bringing this one back from the dead cause the car still has the same problem. Its no where near as bad as it was though. The shop couldnt quit get rid of it. The computer turned out to be bad so they replaced that as well as the O2 sensor and the fuel pressure regulator as i said before. The car will start up great and run nice until i put it in drive or reverse. Then it will die if i dont give it gas while putting it into gear. Once its warm and i turn it off and back on again it doesnt appear to have this problem which baffles me completely. It also never cuts out while driving and is very reliable other than the stalling going from park to a gear or neutral to a gear.

The only thing i can think of at this point is the MAF. What do you guys think?

 

I tried a wells maf on my car. It would stall every time you put it in gear from park, hot or cold. The maf ran the idle too rich. Changed back to original maf, idle troubles left.

 

The other thing im thinking of...and it has been mentioned before is the IAC isnt operating correctly. The shop checked it so it should be fine but i dont think they ever pulled it out and really checked it carefully. This spring or summer im going to start by replacing the IAC with a factory GM part and setting it up correctly and see what happens. If that doesnt solve it im going back to my theory that its the MAF. I had my car dynoed awhile back and the fuel/air mixture was 12:1 i believe if memory serves right. It was a tad rich but very steady at that. The plugs all have a brownish look to them too.