I hope someone might have an idea what is causing this situation.

My car does not smoke nor burn any oil whatsoever!

I recently had my car on the dyno. During my pulls the exhaust was clean, no smoke nothing unusual or out of the ordinary. Now after going WOT during the pull in drive and letting fully out of the throttle after about 1-2 seconds, while car was winding down I would get a large puff of white/blue smoke then it would clear up.

It was suggested to me that the large amount of vacuumn created by sudden deceleration while the torque coverter is locked up and the car is winding down on the roller would create the vacuumn effect and suck some oil through the valve guides.

Basically going from sucking huge amounts of air through the intake manifold at WOT to the car actually backing down on engine compression makes this effect.

And yes it was oil smoke you could smell it, it was more whitish than your usual bluish smoke. No it has nothing to do with coolant or head gaskets.

Any ideas? I hope I articualted this well enough!

Ken

 

mine does the same thing if I rev it up over 3k. It wont happen if I hold it there. But once I let off, smoke comes out. But evreytime I generally start the car up I get smoke that comes out. Which leads me to think valve seals. I think you have the same thing. Does a lil bit of smoke come out on start up?

 

Nope, no smoke on start up, no smoke under normal acceleration nor under WOT on the street.

It does not do this at the track either. It only does it on the dyno. As the car is winding down with backpressure from the engine, as the torque converter is still locked up it will blow smoke!

I am wondering if it has anything to do with a bad PCV valve?

Ken

 

Smoke after a long deceleration sounds like it is sucking oil through the valve stem seals. I had a Ponitac with a 389 that did that. Only smoked on one particularly long hill. Problem went away with a valve job.