I have a 1998 Nissan Altima. 135k miles, timing chain replaced, ALL of the seals replaced (except the valve stem seals), new clutch, the whole nine yards.

When I rebuilt this motor I was running into what I believe is crankcase over pressurizing. After running at about the same load at the same RPM for more than 5-10 min it would lose a cylinder and start smoking oil.

At the advice of a mechanic I have replaced the valve stem seals, had the oil changed, and had the pcv changed. Now, for no reason that I can put my finger on it will start to do the same thing only with mostly a gas smell in the smoke. If you let it continue for more that a couple of seconds it will start to drip gas out of the tailpipe!?

After a compression test it ran (mostly) fine!? You could tell that some cylinders where low.Compression test results:

Results are in PSI. Cylinders read left to right looking from front bumper.With no oil in cylinders #1-115 #2-126 #3-161 #4-160With oil in the cylinders #1-117 #2-127 #3-166 #4-169

My question is what have I missed!?

hey would u happen to have ur service engine soon light on? If so have you gotten the codes read, and if you have what are they? Im asking this because I've had similar symptons with my 98 Altima with the same engine. But my car only does it when I run the air conditioner for an extended amount of time.