smoke from exhaust

[turbobooster]

this is to help a friend out that drives a hot air he just had his motor rebuilt n turbo no oil leaks has a rough idle but runs hard n strong at only 10 lbs of boost w/external wastegate says he has his fuel pressure set at 45 still runs stock 84 ecm this is all the info i have for now he is letting white smoke out of his exhaust pipes which he says is oil smoke "BUT ONLY" wen he gets off the gas wat can b causing this ?

 

[UncleDave]

Did you say turbo was rebuilt? Smoking when you let off sounds like the turbo oil seals are leaking. The right seals are important on a hot air because of the draw-through setup, when you close the throttle abruptly there is a pressure differential that can suck oil into the intake side. I had this same symptom years ago, and that's what it was.

I am by no means an expert, and this may or may not be your issue, just wanted to throw it out there.

 

[turbobooster]

yea his turbo was rebuilt as well not sure by who though thanx for ur input uncledave

 

[RegalT-type85]

It could be your turbo seals as stated above, did you change to a lighter oil or use an oil additive recent? Is your PCV system working/new? Crankcase PSI build up will push oil out gasket, seals etc

 

[turbobooster]

so even with him running only 10 lbs of boost the seals can still go bad?

 

[RegalT-type85]

i think 10lbs is enough but replace your pcv valve, If you have a breather on the valve cover(open k&N type) check to see if it's oil soaked.