About a week ago, my car started to smoke while it idles. It only smokes at idle and when its warmed up. As soon as I give it any throttle, it blows a small cloud of smoke then nothing until it sits at idle again for a min or so.

It doesnt do it on start up, or when revving up. I've never had one do this before so it has me stumped. Any clue what might cause this?

The car is a '94 Z28 with about 130k on the motor.

 

What color is the smoke? Black, blue, white? How much?

 

Looks to be white/blue.

Its not much, just barely enough to notice until i give it some revs, then it blows a small cloud. After that its ok unless I let it idle another min or so, then it starts back to the same thing.

 

Hmm, I'd be curious to see what others think but it sounds like leaky valve stem seals.

 

i have a 1994 z28 also, and ever since i bought it mine has done the same thing, and mine also has 132,000 miles on it. i Haven't really worried about it.

 

Well im starting to think it could be the head gasket.

Its been losing water for about 2 months that I cant seem to find where its going. Its not a lot, maybe a cup or 2 each week. I just thought it was leaking out somewhere that I couldnt find and with it being an older car I wasnt too worried about finding it as long as it didnt get too bad.

I'm going to pick up some block sealer tonight after work and see if that helps. Hopefully if it is the head gasket that will hold it until I can get a new motor built for it.

 

Does the smoke smell sweet like coolant?

 

Not that I remember, but to be honest I didnt really think about the smell.

I'll check and get back to you later this evening.

Could it be the valve stem seals? I've never seen them go bad but not smoke when the engine first cranks.

 

OK so just a little update

The smoke is blue and doesnt have a sweet smell.

The PCV vent hose is blowing some oil residue into the throttle body, which I'm thinking might have something to do with the problem. I'm going to delete that line and just put a breather in its place and see if that helps.

Thanks for the help so far guys