1983 Pontiac Phoenix - 2.5L Won't Idle

[92zman]

This car came in on the hook found then the computer had been holding the inj open and dumping fuel. When replacing it found out then it had the wrong year of one in it. Car will drive fine but will not idle in p/n; in all other gears it is fine. Have tried both s/n of computers one it came with and the one it says then it needs to have. If i put it in limp in mode it will run ok. IAC is not doing it i can unplug it and it keeps going. What it is doing is going up and down in idle and most of the time it will die. When cold it is fine until it gets warmed up.

[Pauls Automotive]

It sounds like you have a vaccum leak. Have you looked to find one yet. I usually spray some gum cutter around the inake to see if the idle rises.

[steven kiser]

If i recall correctly there was an issue of the egr solenoid sticking on and keeping the egr open. When it's cold it's rich enough to keep it running however when it warms up and leans off it will stall. There were issues where the intake gasket would dry out and fall away on either the #1 or #4 cylinder. It was usually on the under side. If this is the case it's fairly simple to replace it. Drain down the cooling system and with a little work you can get to all the nuts and bolts, back off the manifold, gasket usually falls away and there is enough room to fit in the replacement and lift manifold back into position.

[jbadenoch]

I think you have the year wrong,

[92zman]

found one vac leak still will not idle. Have checked year and all that with dealer. There was two computers in that year have both here one it will run but wont idle the other it will ot run. With the one in for the 82 it will not idle and if i scan it no tps coolant is going up and down but with the early 83 in there all looks good on data. Was trying to remomber thought there was a idle learn to do to this thing after battery was out and stuff like that. Was keeping it running and seen the spary of the inj is not good checked fuel psi and that was about 14 psi and when u rev it up it falls on it face then will start to go up.

[brother bubba]

....

If I remember correctly, idle learn occurs after you get up to 40 mph and then back off.

...

[jbadenoch]

Fuel pressure spec says, 9-13 psi. 1/2 pint in 15 seconds. Sounds like you have a fuel pressure issue, however it shouldn't be causing no idle. Computer should re-learn idle if you drive at 40mph for 2 minutes.

[92zman]

Ok going to have to go drive. Did check egr and all that seems good. Any one have a control mod do some of this stuff. Some times when i am trying to keep it running it seems to be out of time. Need to check have not put a light on it yet. Sucks get one of this old things and forget how to work on them...

[92zman]

Ok have checks and cleaned all grounds. Got 1.0 ohms at computer. It is getting worse as i look at this thing. The sparyfrom the inj is not good but if i trigger it my self it is good. Fuel pump flow is good. Checked wire from computer to inj and it is good. Has anyone seen a control mod do this.

[Stewart Levy]

Did you verify the prom?

[92zman]

how

[steven kiser]

At one time there was a list available through the dealer that listed the latest prom. I don't know of any that weren't updated and some needed sensor replacement as well. Usually there were under hood stickers or stickers that were supposed to be attached to the pcm.

With the scanner attached look at the readings and watch coolant temp and the 02 readings. Not sure but i think that there was an issue with the throttle base gasket cracking. See if the base or curb idle screw has been messed with ot the idle tab has been bent. Remove iac and see if there is carbon between the pintle and seat. It's obvious because you should be able to see a clean ring all around the pintle. Another quick tip is while it's running see how fast the selector works for the heating vents, a quick vac test. If i remember correctly there were issues with the vac reservoirs cracking.

Just took a quick tour through memory lane and i had completely forgotten about the most intricate most used test for p.c.m.'s. The tap test. While engine is running tap the p.c.m. with a wrench or extension. If there is an intermittent problem with it tapping it will make it run better or worse. I've had them stall right away or start running great. I also saw more than a few tsb's about an updated tps. While it's running if it sounds like a jet engine attach a timing light to it and look at the pattern of the tbi. If it's solid with no break tap it. If it changes you may have a bad injector. This can be caused by a warped throttle body. I can go on and on about this one. Once my grey matter gets locked in on it and clears up it amazes me. Call me on Monday. tsb # 86-6

[92zman]

Ok will put in a control mod and that did nothing. Here is the thing the computer that was in the car is for a 82 S/N 1225610. Put one in and car left for about a week. Came back and when i put my scanor on it the coolant temp in going up and down at all times. And i have no tps so replaced it again and the same thing. Started looking at other ideas and founf then if i put a computer for a 83 early in there i have everything on the data list lookes good but the battery volt. It is 0. And will not idle at all. Was running good in gear and now it will not. Found some vac leaks fixed them cleaned grounds even added a new body ground. With the 82 computer in there the inj spray is good but data list is all messed up but with the 83 in there it is very weak. Prom # 6672 by them two computers but if i put the old one out of the car back in it reads 2256 i belive. The frist computer when car came in would hold inj wide open. Car will not run long enough to find any other vac leaks. Hope this can help someone help me i am way at a lost. Customer say then the car only has 33000 on the car. Dont know. I have went though all my notes from years ago when i was working on this things all the time.

[92zman]

Got to look at the car some more today and found then the qurd driver in the computer is what was going out.Checked out more and found then the A/C coil was going right to ground. I feel so dumb!!!!!!!!