Here's my problem:

The car started smoking when cold. It happened quite suddenly, i.e. it has't been getting progressively worse.
As coincidence would have it, I did have the top of the engine disassembled for a few days while I was doing some work but I haven't done anything out of the ordinary and I can't figure out why it would start smoking.

It started right after I reassembled everything. I changed the chip to run a bar II sensor because I have a turbo. When I saw the smoke, I changed the chip back to original and changed the sensor back to bar I but that didn't help.
Other than that, the engine is pretty stock with a performance cam.

When I start the engine, there is no smoke immediately thereafter. It starts about 20-30 seconds later.
Then it smokes like crazy! The smoke appears to be white-ish / light bluish. It goes away once the car is warmed up.
It slowly subsides as the temperature goes up.

I'm puzzled. Could it have anything to do with the cold start injector?
The check engine light has not come on.
All of the connections seem to be fine too.

How do I know if it's oil or if it's excess fuel? I've taken it for an 800 mile trip last weekend and it doesn't seem to be burning oil (at least no more than normal).

Any suggestions would be greatly appreciated.

Thanks!!

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Could you give more detail as to how far down you took the top of the engine to. Didi you take off the heads?

I have taken off the plenum, throttle, distributor cap, EGR hose and some cooling lines only.

I've had to remove the turbo and parts of the exhaust.

I had the turbo rebuilt. I'm told that the turbo does not in any way affect oil / fuel burning (not at idle, anyway).

Does the smoke smell like oil?

If it's oil, the only variable you've introduced is the rebuilt turbo. Is it possible that the turbo could be leaking oil past the shaft seals into the intake? Or might it be the PCV valve or part of that system?

quote Originally posted by Raydar: Does the smoke smell like oil? If it's oil, the only variable you've introduced is the rebuilt turbo. Is it possible that the turbo could be leaking oil past the shaft seals into the intake? Or might it be the PCV valve or part of that system?

Hmmm... I never thought about the PVC valve.
I'll check it.

As far as the turbo, I'm told by some 'experts' that it's not possible during idle because it's not spinning. I don't know enough to dispute this. Plus why would it stop once the engine is warm?

I guess I'm not sure what burnt oil smells like. I suppose it *could* be. Then again, I used to think that my stinky exhaust was oil until the guy who installed my turbo system said it's gas because he purposely adjusted it to run rich (until I can get it tuned properly).

I'll go back to the turbo rebuilders and ask, though. Again, unlikely at idle but who knows?

Thanks for the suggestions so far guys!!

Any other ideas?

I'm going to say to replace the PCV first. Always start with the simplest and least expensive possibility. I had a Chevy Blazer (no turbo) that did exactly the same thing. Replaced the PCV and no more smoke. As to why it did this I don't know and it didn't concern me as long as the smoke went away.

What sort of lubrication is your turbo using?
I think the unit spins at idle as there are gasses (exhaust) passing the vanes even though a small amount.
You say "It goes away once the car is warmed up." makes me think it is from the turbo lubrication. Are you sure the housing isn't cracked around the bearings?

Thanks guys.

All good points.

I'll start with the PCV and then I'll go and talk to the turbo rebuilders. See what they have to say.

I've been told the turbo shouldn't matter at idle because it's virtually not spinning. I would have thought that it would smoke more once it got spinning.

Anyway, time to do some diggin!

my '88 2.5 puts out white smoke for about 5 city blocks after setting in the rain over night or several hours of rain, am thinking that it has to do with air pressure, moisture in the air, and cooling exhaust system etc, and heating moisture into steam 'smoke' till exhaust system is warm/dry. never does it in dry weather, and rad is always full when checked...

Where is this smoke coming from? Out of the exhaust, or off of the engine itself? A turbo will always spin when the engine is running...the speed of the impeller is controlled by the exhaust of the engine. It IS possible that, as Raydar said, the seals are bad, and it's drawing oil into the intake. Hard to say what it is...would help if we knew where the smoke was coming from.

quote Originally posted by litespd: Where is this smoke coming from? Out of the exhaust, or off of the engine itself? A turbo will always spin when the engine is running...the speed of the impeller is controlled by the exhaust of the engine. It IS possible that, as Raydar said, the seals are bad, and it's drawing oil into the intake. Hard to say what it is...would help if we knew where the smoke was coming from.

The smoke is coming right out of the exhaust.
But why would it quit once the engine is warm?

quote Originally posted by Voytek: The smoke is coming right out of the exhaust. But why would it quit once the engine is warm?

It does it until it's completely warmed up, or just for a bit? It almost sounds like bad valve seals, except for the fact that it doesn't do it immediately upon startup...

Sounds like it could be the turbo leaking oil on the exhaust side while sitting. Once you start the engine the exhaust heats up and burns off the oil inside the pipes. That would account for no initial smoke.

Well, I took out the PCV valve first (since it's the simplest) and it appears to be sticking really bad !

I'll start by changing that today and see what happens.

If that doesn't work, the turbo will be next.

BTW, it's not the valve seals. I have seen that time and time again on other cars and the symptoms are quite a bit different.
Thanks for the suggestion, though.

quote Originally posted by El Guapo: I'm going to say to replace the PCV first. Always start with the simplest and least expensive possibility. I had a Chevy Blazer (no turbo) that did exactly the same thing. Replaced the PCV and no more smoke. As to why it did this I don't know and it didn't concern me as long as the smoke went away.

It was the PCV valve!!!
The little ba$tard was sticking badly.
Your suggestion was right - you've got a big + from me.

To all the others that offered help - thank you!!!!!!

quote Originally posted by El Guapo: Always start with the simplest and least expensive possibility.

Sage advice ... worth repeating over and over again!

Check the Turbo oil return line. If it doesn't have a continuous path downward to the oil pan then oil will seep past the seals and you'll get smoke.