Here's a question for the Tech's

Ok off the top,
This is re: a 1992 Chevy Cavalier 2.2 "throtlebody" AT.
This things baffling me and another garage and I'm just about disgusted.
The car runs but has a slight miss at idle. Its not a steady miss its rather intermittant.
But when you try to accelerate with a load on the engine while in drive you cant get past an average of 20 mph without the engine:
A: either its running too lean.
B: its flooding itself.

I've Once had the check engine light trigger but it cleared itself about 2 minutes later. tried retreiving any codes with a snap on scanner but no codes. "it doesnt help this being OBD1 technology" =(

Sofar I have taken out the catalic converter and punched it out.
I changed the fuel filter, upon suggestion from a mechanic thinking its running lean I "just" changed the fuel pump and module.

This has only seemingly made the problem more apparent.
What I can see now is the plugs, Unsure of the firing order on this car but from left to right the first 2 cylinders are slightly carboned up and the other 2 are Clean.

Any sugjestions.?
I'm going to pull another coil pack off of my newest addition to the garage, a 1991 Cavalier Euro that had a blown head gasket.
Hoping that this may end with either a coil pack or ignition module.

1st: clean the IAC valve, and fuel injector. Either one could be sticking.
2nd: check your TPS. could be sending bad signal.
3rd: check for vacuum leaks(gaskets and hoses), maybe swap the MAP sensor just to check.
4th: Plugs, wires and coils.

I took the coil packs and ignition module from a running car and tried it and still the same.

I'm now wondering what the symptoms could be if this was a bad high pressure fuel regulator. If I disconnect the vacuum line to the regulator the problem gets worse but its been all too intermittant to tell.

i had the same problem with my '97 cavalier, one of the spark plug wires had a rip in it and it was arching off the side of the head every once and awhile, and that caused a miss

Well,

this is worse than a miss. Its just plain out and out hardly runs. I did go ahead and finally took a compression test.
cylinder 1: 154psi
cylinder 2: 67 psi
cylinder 3: 160psi
cylinder 4: 155psi

So, from the looks of it I'm thinking the car has possibly blown a head gasket but I have been unable to locate any signs of blowby or anti-freeze leaking. Or could I be beating the wrong horse and just have a bad set of rings...

Sugjestions?

cars got 112k miles, Paid 500.00 1yr 4months ago.. so I've gotten my use out of it.. but now I spent 210.00 on a fuel module and pump.

planning on working on re-installing the head on the 91 cavalier today and driving that for now.

if it is sometimes running too lean and soemtimes running to rich.check the O2sensor..

an emmissions problem is about the only that will trigger a check engine light. it is the only thing that will in my cavalier, and it says so in the owners manual.


if the o2 censor is reading in accurately the car will use more or less fuel to get the right mixture. if its the wrong reading, adjusting it would therefore create an improper mixture.