Smoke, Smoke, Smoke

[JimFestiva]

My 93 automatic was working fine. It has always smoked some, but now smokes continuously. Not just a little bit of smoke either. I am sure the engine is near life end. It does have some seal leaks where I am losing oil, but the combination of oil loss before the new problem was a quart per 150 miles.

I have not had enough miles to get a good reading, but is seems to be about the same given the small amount of driving that I have done on it

Other than the smoke, it seems to drive about the same.

Any ideas?

[Damkid]

Bad rings probably, hard to say for sure without a compression test

[JimFestiva]

Thats my guess. I was just surprised it went from some to a lot in a matter of minutes.

[Damkid]

Try a compression test and go from there.... That's what I'd do at least lol

[georgeb]

Might have cracked a piston or ring. Do comp test then add a bit of oil in spark plug hole and redo. Will come up if ring issue.

[JimFestiva]

I will give that a try. Never done a compression check before, so it will be a first for me.

[Ape]

Real simple job, Autozone/Advanced Auto or O'Reilys will rent you a Compression Tester.

YouTube Video. How to do a Compression Test

[WmWatt]

What colour is the smoke - black or white?

[JimFestiva]

It is mostly white. It still has a smoky smell. I don't seem to be losing any coolant.

[Bert]

If your PCV valve sticks the crankcase pressures can force oil into places you wouldn't expect and result in increased smoke. See if that valve is clear and check the line going into the valve cover to see if you can easily blow through it.
Whatever you do don't give up yet. Wet/dry compression test will give you lots of information too. WmWatt's advice about smoke colour also is useful; keep an eye on antifreeze levels just in case there is a blown gasket.

[JimFestiva]

I'll check out the PCV valve this afternoon. I am going to try and do a compression test this week. Thanks.

[JimFestiva]

I check the pcv and tube. Both are working fine. What I did notice, which may be normal, is that the tube to the intake has quite a bit of suction with the PCV removed. The head also has a fair amount of pressure with the valve removed. With the valve removed, I have to place my finger partially over the hose for the car to not stall.

Like I said, I don't know if that is normal or not. I do suspect that there should be pressure so much coming from the engine.

Could any of this be related to exhaust backpressure? Maybe a bad catalytic converter?

[WmWatt]

A plugged exhaust will show up on a vacuum guage. See the permenant thread at the top of this page on diagsnosing with a vacuum guage.

When my last car made white smoke it was rings.

[JimFestiva]

You would think for $500 you wouldn't have these kind of problems. (ha ha)

[miami man]

long shot but years ago i bought a 71 chevell that smoked alot and come to find out that some of the oil passages in the head were clogged and the oil was not returning and being sucked in throgh the valves and i took a coat hanger and cleaned out the oil returnes and it stopped smoking