Alright, I have an '88 iroc with 350TPI thats been acting strange recently. I was driving to a friends house, no problems the first half of the trip. I made a quick stop, when i started it back up roughly 15min later, it starts fine, i pull back onto the road, go a mile and catch a redlight. As im sitting there, it just stalls. I try starting it, it wont start. I let people pass, try again, it starts up fine. Check engine did come on, but being i was in the middle of a busy road i didnt have time to check for the code. Once started, the code dissapeared/SES light went off and stayed off.

Fast-forward 10-15 min no troubles, after the light turns green i give it some gas, the SES light flashes & car stumbles but doesnt stall, and comes right back to life within 2seconds. I make it there ok, then when i leave it did the same thing once on the way home (after light changes, i give it gas & SES light flashes & car stumbles but doesnt stall).

I was getting in my car 2 days later to go to work and when I start it it starts ok, light immediatly comes on but runs ok. I shut it off and ran the codes and got 36 &51 i believe (it was prom error one). I had my gf take me and pick me up from work in fear it may stall on the way there, and independance blvd (in charlotte) is not a road you want to stall on. When i got home I unplugged-replugged MAF, pushed up on the prom trying to ensure good connection, reset the codes and took it for a drive. It ran great, loads of power, no stumbling, nothing. Then I saw a friend walking as i was test driving so i pulled over and talked to him for a few, after 30sec or so he says "nice car", i say, "Thanks, its alot of fun to drive--- it stalls. Pretty embarrasing i will admit! haha, I check for codes, nothing.


Im really not too sure what it could be, i was thinking possibly:
-TPS flaking out
-Coil going bad
-CTS maybe?
-ICV?

I checked the TPS and its fine, .54V and wasnt jumpy when i slowly gave it throttle.

I dont really think its the prom (hope not at least!) i think thats more of an intermittent thing (of course, so is my problem apparently.

I havent checked fuel pressure, but my car has brand new fuel pump, strainer &filter, gas tank and sendng unit even. 2< monthes old, and fuel pressure was perfect at time of install. Besides, at high rev it still pulls like an animal anyways, so im 99% sure its not FP related.

I checked for vacc leaks for the heck of it but found nothing.

I appreciate all help, i am a bit lost and could use some ideas/suggestions.

Thanks!

 

My Z did the same thing, unfortunately it was the injectors.

 

sounds like it could be the temp sensor for the computer. if it tells the computer it is to cold it will load up on fuel when you let off the throttle.

 

I would suspect faulty ecm.

 

Sorry for the late response, i havent been on in a while.

Well, i almost got on to tell you guys the problem went away, but it seems to be back after over a weeks' haitus. Today i was driving and it was great, just like its been for the last week. No troubles, ran perfect. I go to my gf's house and when i leave, i go over a speed bump and the cars dead. I pull over and run the code, and i swear it gave me 11 (???) and 12 (i know is normal). I try starting it again and it starts perfectly, like nothing happened.

Then, continuing home, the SES light flashs, lose power but it doesnt die, then its ok again. I even romped on it a few times trying to get it to act up and all it did was sink me into my seat like it always does! So i get home ok, and go for a test drive later, it doesnt stall but the light flashed once, it lost power worse than usual, then came back real strong. Again, this was right as i hit a speed bump..

I checked the battery ground to the engine block and its good, are there any other grounds I should check, just to be sure thats not a problem?

If this was an ecm problem, wouldnt it give me an ECM code? (47, 52, 55,66, 88, or for prom, 51?)

If its the coil going bad, theres no code that tells me right? I looked on the list and didnt see any, so that would mean this is still a possibilty.

I will check the injectors and CTS as well to see how they are. I tested the injectors a few months ago and they all checked out ok, but ill double check them now, you never know right?

Thanks again guys

 

check the grounds on the passenger side head in the rear of the head.

 

Alright, will check in the am. Thanks!

if thats ok, what would you try next?

 

if you have a 51 I Have never seen a memcal go bad, the wrong calibration memcal from the wrong vehicle will cause a 51 I would suspect the ecm after that.

http://www.ebay.com/itm/AcDelco-1619...3#ht_500wt_951

 

There are alot of guys parting out tpi camaros in the classifieds here you may pick up a ecm for cheap 86-89 all use the 1227165,16198259,16198445 just install your memcal.

 

Ok, thanks, thats a good idea.

Well now it finally threw the codes long enough for me to stop and check them. At least now i know the problem!

They are:

42
43
51

I know 42 and 43 are related, the ESC. It says low voltage to the ESC. What would cause this? Could a bad coil? (not trying to harp on the coil thing, just hoping its as simple as the coil, and id like to replace it with a performance one anyways)

51 is prom error i know, would that be related to the ESC problem?

I dont even know where the ESC is on these cars, is it under the dash? Where so? What should i check?

Thanks again for the help guys, i appreciate it!

 

Anyone?

 

http://chevythunder.com/maf_esc_module_code_43.htm

http://chevythunder.com/est_code_42.htm

A few tests for you, yours is the 1227165 ecm.

 

the esc module is on the drivers side next to the fender well on the bulk head.

 

Well I found and unplugged/plugged back in the ESC and for the last 2 days i havent had a single problem with it yet *knock on wood!* It hasnt flashed, stalled, or anything.

I do have a question though, I noticed theres a relay (far right) that isnt bolted down very well, it never caught my eye until i messed with the ESC. Theres a pic below:



Whats that relay for? I looked for any bolts i could use to hold it down better but i didnt have any, but the one thats there holds it fairly well. Im not happy with it, but i think it seems to be ok for the time being. Im conserned about how well its grounded, but what does it do anyways? thanks

 

that is the fuel pump relay, the metal tab is not the ground for it its just the attachment point for the relay. you just need a couple of self taping screws to better secure it.

 

Ok, cool. Thats good to know. I have another question, but im going to start a new thread for it. Thanks for the help, maybe you can help me with the new one too!