Excessive Crankcase pressure.

[G60 Carat]

Ok last time I had this, I had low compression on 2 cylinders and found the ringlands were all busted out.

This time I did a compression test and had 155 across the board, but my crankcase pressure is very high. It looks like exhaust smoke coming out, the boost pipes are coated in oil. and the car sometimes puffs blue on start up.

I'm assuming the engine is knackered again, but are there any other things that can cause this excessive pressure.?

[chc-rado]

Pistons rings are worn out, or worn out valve guides too. Have you check your spark plugs condition. Like oil deposit on them. Also check there no blockage on breather system too. How many miles on this engine? What has been done to it. If it was rebuilt, what has been rebuilt or refreshen?

[G60 Carat]

Fresh Engine in 2009.

re-used old pistons/block, but new rings, rod bearings, mains, all seals. Head refreshed with new guides and viton seals. Original valves, just cleaned up.

I did recently have a big dirty nitrous backfire, and I suspect it may have damaged either a piston or headgasket.