jwscab

OK, heres the scoop....1987 iroc 350. car ran fine until one day, wouldn't start after an hour ride, just after got fresh tank of gas. Tried later on in that week, and it started fine, but would stall anytime you put it in drive or reverse. Went on a spree of changing new parts as follows:
-new CTS
-new IAC
-swapped MAF with known good
-reset min idle
-had to replace valve seals and intake gaskets due to coolant leak, changed EGR valve.
-tried removing all vaccum hoses as possible leak
-EGR solenoid checked and OK
-emptied tank, put fresh 93 in
-TPS OK
-new module, spark plugs, cap rotor(wires OK)
-new fuel filter, fuel pressure good at all throttle posistions, maintains about 42 psi.
car displays somewhat rough idle at around 750. funny thing is, sometimes, it will fire, and run up to 1100 or so, and idle will be a little higher, as soon as you rev , or put in and out of gear, idle will drop, and be somewhat unstable. when cold, runs good, until cold start inj goes off. I'm thinking that possibly a bad injector, or one on its way out, i'm going to try unplugging one at a time. When I take the car for a ride, I have to double foot it, with my foot ever so slightly on the gas to keep from stalling, but it runs fine off idle. Does anyone have experience similar to this? Any suggestions before i dump it in the river? thanks in advance. Oh yeah, I've put a scanner on it, and nothing seems to be out of the ordinary, temp, tps, etc all seem normal. One other weird thing, I noticed that now my volt guage in the dash reads alomst 18volts(in the red!), but when i measure the batt voltage while running, its dead nuts 14.5V, so there nothing wrong there(only in the dash). I also tried removing the charge lead to see if there was some weird electrical load. No change. thanks guys for any help......

FU-Q

funny your talking about dumping it in the river, im having similer problems and been thinking about rolling it off a cliff...
anyways mine was doing this before and after replacing the fuel injectors, spark plugs, rotor and cap, and spark plug wires. i took it to a dealer and they found the ignition modual was bad, i replaced it and about 2 1/2 weeks later it started doing it again. is your coil resistance up to specs? im going to pull mine and replace it to see what happens. i notice my fuel pump seams to run a little longer than normal like there is a clog in the fuel system im gonna replace my fuel filter and pcv valve (It's due for a change anyway.)
when i have to pump the gas to get it to go my dash seams to dim too but my voltige meter says it's ok.
i am also gettin code 13 oxygen senser. i hope this helps.

jwscab

well, actually, I tried a few more things, that i forgot to mention. I changed the PCV valve, put in a new oxygen sensor, and I actually swapped out another coil. I even changed the esc module, and with each change, the results were exactly the same. go figure. I'm thinking though, that maybe the injectors are very dirty, so at low pulse width, I'm not getting enough fuel, or maybe I just have the idle set too low(set the min idle to 550 rpm, too low?). As for your car having dim lights, I'd check the GND connection on the battery, probably something I should check too. If I find out any other info, I'll post it. These stupid problems are tough to track down.

richie rich

You said you had to replace your intake gaskets and valve seals because of a coolant leak? Where was the leak? I saw a older car do this and the problem turned out to be a bad intake. Did you ever run the car hot? If not are you possitive the the intake bolts have been torqued properly and the gaskets took? Hope this can be of some help as I have been through this sort of thing before.

jwscab

yeah, i had to replace the intake gaskets anyway, as there was a coolant leak on the front passenger water port. Not real drastic, but all that funny white stuff was showing, but the car was never overheated. I figured, since the coolant passage seal had leaked(did stop it with stop-leak powder for awhile), maybe there was a vacuumm leak somewhere on the gasket, they were the original ones. While I was at it, I fixed the vavle seals to get rid of the typical puff of smoke on start-up. The good thing over all that is that the car reacts exactly the same way, so the chances of having a vacuumm leak there twice is pretty unlikely. Gotta keep trying more things.

Justin91RS305

Sounds like your Torque Converter Clutch is sticking if it dies when you put it in gear.

jgifford

I have an 86 z28 that had the same problems with car stalling on idle, and I chased it down and ended up replacing every sensor in the car and it turned out to be one of the MAF relays, I'm not sure if it was the burnoff or the other, but you may give that a try before dumping it in the river.