Smoke Test Pro's... help

This question is actually for the smoke I found. I already have a thread started for the truck. This is for my 2002 Chevy Avalanche with the 5.3. My fuel trims are high like I have a leak. I've done the carb cleaner, brake cleaner and water test and nothing. I put the smoker on the motor, going through the brake booster hose, and still see no signs of smoke anywhere. But taking the oil fill cap off it was full of smoke there inside the engine. Is that because I still had the PCV hose still hooked up? Just found it odd.

Does fuel trim get better with RPM increase? At 2500 and 3500?

Clamp off the brake boost and see if it corrects just to rule that out.

I smoke through the intake when looking for vacuum leaks, throttle should be open. Smoke right behind the MAF as anything behind the MAF is a possibility for a vacuum leak.

If your rpms don’t improve with engine speed you’re likely looking at an 02 problem, an exhaust leak, or a fuel issue.

Smoke coming out the oil fill port can get there one of two ways. PCV or Piston rings.

Thanks John... it's a long story on this truck. Well, as I gas it the LTFT go low but the STFT balanced it out, keeping the total at 25% on both sides. I was a parts changer on this one and I still have the problems. Just changed the But I just needed to know if the reason the block was full of smoke was because of the pcv vacuum line.

Thanks

I was thinking about this one the other day too and I think on a cold engine, if you let it smoke long enough, you'll get smoke in the crank case past the open valves and through the rings. Someone correct me if I'm wrong.

That's with the PCV isolated.

yes, its normal for the crankcase, and valve covers, ect to get smoke.
great way of checking for vacuum leaks/oil leaks, in valve cover gaskets, ect. is with the smoke machine

remember, a oil leak is a vacuum leak regarding engines