Smoking at W.O.T.

[Rosamond SVO]

O.K. I need some help. When running in Premium in 1st gear after about 4000 rpm 16 psi boost, there is black smoke behind me (looks like a turbo diesel with the fuel turned up). I thought that it might be the turbo leaking oil under boost, but no oil in the intake. I have been driving it easy for the last month trying to save up for a new turbo. This morning on the way to work I did some trouble shooting switched to unleaded started off hard from a stop got up to 4000rpms at 12 psi boost no smoke. Them went back to Premium at the next stop sign and the smoke was back (could not see the care behind me. So with that being said any ideas? O2 sensor, computer, fuel press regulator?

[Rosamond SVO]

Let me add that i just changed the exhaust manifold gasket on Fri because it was leaking, the bolts were very black from soot looks like it has been running very rich for a long time. Rebuilt the motor in Feb so I could take it to las Vegas.

[Under Pressure]

Black smoke oil. When the engine is cold and you start it see if it smokes a lot. As it warms up see if it cuts down on how much it smokes. If it clears up as it warms up then it's going to be valve seals or valve guides or both. If it smokes heavy all the time you got a broken ring or bad piston. Pull the plugs and do a compression test.

[Mike S]

Black smoke indicates excessive fuel. What is your fuel pressure set at. A dirty VAM could also cause more fuel to be dumped out the exhaust. Pull the vacuum hose off of the FPR and see if you have gas in the line. Remove and clean the VAM and intake track. Verify that your ECT is operating within range by pulling codes. Codes should also expose any other sensor problems. Double check you TPS settings.

[Meotchh]

Also wondering why you choose to install an exhaust manifold gasket?

[Under Pressure]

I got that turned around, old age.

[Rosamond SVO]

To answer some of the questions the eng was rebuilt about 8000 miles ago, and to only smokes at W.O.T. in premium mode. I will get a fuel press gage and check pressures. I will clean the VAM this weekend to see if that helps. Thanks for the input.

[JTurbo]

My SVO did the black smoke thing when I first got it, turned out to be the original FP reg took a dump (pressure was way too high). Bought a Kirban adjustable regulator and it's been fine since....

[Rosamond SVO]

So here is a update. I know it has been a long time almost 2 years but here is what I have done. Changed the VAM still smokes, tune up still smokes, changed O2 sensor still smokes, changed the fuel pump last weekend because it would not hold press when not running. When I took it for the test drive the TFI went out. Changed the TFI still smokes, changed the Coil last night no more smoke. Problem solved. thanks for reading sometimes its e little things in life.