Blue Smoke [Merged 7-9]

[WhiteCloud]

After driving from Charlottesville, VA to Gainesville, FL to visit my best friend for his birthday, I got back into stop and go traffic in the city and noticed I was puffing some blue smoke when taking off from a stop. I'd never noticed this before the trip, so I'm inclined to think something during the trip caused it.

Symptoms:
1) Puffs a cloud of blue smoke shortly after revving engine in neutral.
2) Puffs a cloud of blue smoke while taking off in first gear, but not always noticeable.
3) Doesn't trail smoke like it would if it were a head gasket.
4) Turbo doesn't seem to have excessive shaft play, and boosts fine.
5) I'm burning some oil, but not a tremendous amount (I burned maybe 1/4-1/3 of a quart on the 700+ mile trip back to VA from FL.

I'm wondering what you guys think the problem is, judging from these symptoms.

I've been told to check the PCV valve, but I'm not exactly sure what I'm looking for (in terms of oil, residue, etc. on or in the valve!?), or if I should just be replacing that to see if it fixes the smoke.

What would your next step be if your car were puffing this blue smoke? Is there a way to tell if it is valve seals?

Thanks for the help,

Joe

 

[raizen]

There is not many place where oil can enter the combustion chamber. If the head was rebuilt then the seals shouldn't be an issue. The only thing I can think of is the rings or the turbo. Did they machine the cylinders? Usually when that's done they install oversized rings to compensate for the material that was taken from the cylinder. That could be a problem area. But if your compression test checks out then you can breathe easy. The only other thing would be the turbo being bad.

I have always done compression test with the engine warm. Only because as the car heats ups, parts expand. Warm the car then pull the plugs. When you put the plugs back in you should wait until the engine is cold. If you cant wait then install them gently. I have known a few people that stripped the threads on a hot head. Not fun

 

[Unde7277]

Okay so if the compression checks out then It's definentley the turbo. And okay I'll do a test drive then I'll do the compression test.

 

[BogusSVO]

A compression test will let you know how well the Top and 2nd ring seals. But nothing about how the oil scrapers are working.

Running rich, improper oil changes can and will clog the oil return holes in the oil scraper ring land.
When the return ports clog, the oil has no where to go but hang on the cylinder walls and be burnt.

Also the oil scraper rings can get stuck in a bad case and end up not even doing the job they are supposed to do.

This is not the most common issue, but can still happen

 

[Unde7277]

I'm assuming if that's the cause then it will most likely need a bottom end rebuild?

 

[raizen]

Unfortunately yes. But hopefully the compression test yields passive results then you will be able to narrow it down to the turbo or the valve stem seals.

I mean positive results

 

[Unde7277]

Yeah with receipts on the head rebuild less than 3k miles ago I'm not too worried about the valve stem seals. If It has good compression on all 4, and If I check the turbo inlet and there is oil then it's most definentley the turbo. Hopefully all goes well and I end up with a DSM finally after months of searching but we will see.

 

[Unde7277]

so i went and test drove the 98 gst. the car stalls after light boost and I've read up its most likely because the bov is not recirculating it is venting to atmosphere. when the car did stall i would start it back up and the accessory belt would squeal really loud. any suggestions as to why it squeals after it stalls? and the car smoked much more after it warmed up so it leads me to believe that it is the turbo that is blown. he also had a leak down and compression test done and he said he got 125psi across the board and a little variance between the cylinders. the leak down test he had done was that cylinder 1 - 15% cylinder 2 - 10% cylinder 3 - 20% and cylinder 4 - 10%. so other than the low psi, should i be worried about anything else? thanks guys

Also I got him down to 2400$ so let me know if that's worth it