1993 chevy cavalier 2.2 litre has eratic idle, fouls #1 plug?

Question

1993 cavalier 2.2 litre idles eratic. coil pack ohms good, new spark pug wires-good ohms, 140 pounds of compression. it fouls the number one spark plug. i still drive it for work, but it has become a pain to drive. the motor smooths out in the upper rpms. it has 228000 miles. it is a manual trans. i cant afford another vehicle atthis time. i am a decent mechanic, but this problem has me stumped. any help is appreciated. thanks

Answer 1

I own a shop, and have worked on these for years. I sure sounds to me like you have a bad worn valve guide, and/or a leaking valve stem seal letting oil into the cylinder. You can run a vacuum test on the engine to help narrow it down. 140 pounds of compression is good so I wouldn't think the rings have let go. One with this many miles on it may have a worn out camshaft, thus making it run rough at idle, and tend to clear up when you get on the road. A pin hole in one of the lifters will also do this, as in the lifter worn so bad it is mushroom shaped on the contact area, and a hole has begun to rear its ugly face causing the lifter to leak down at idle speed. A sticking injector will usually wash down the cylinder walls, and the compression will be down on that cylinder. It sounds to me like you have about ruled out everything else. DO a vacuum test!! This will tell you what is going on with the engine. You could even have a blown head gasket. Oil is getting to this cylinder either down through the worn guide, or head gasket, and fouling the plug. The fouling thing is either caused by oil getting to the plug, or the plug not firing correctly. Doing a leak down test can also help comfirm the condition of the cylinder.
Glad to help out, Good Luck!!!

Answer 2

with that many miles it is probably a burnt valve. but first check the injector. it should put out a cone shape spray of fuel
also listen to it click while running the clicking should correspond with the engine speed. a niod light on the injector will tell if the computer is giving a proper signal to the injector.

Answer 3

Could be you need a valve job, or simply replace the o ring oil seal on that valve. Or you could have a sticky injector that is not operating right and pouring in gas instead of spraying it

Answer 4

Probably a bad valve if it is also burning oil. It doesn't come as a surprise either with that many miles on it.

Answer 5

This may sound stupid,but have you had the head bord out?If not try get the head bord and see if that stops it from fileing out.Use to be married to a car jockey.