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Hi guys just back from a 700 kilometre round trip to Tamworth. After a spirited short down hill my Nba was blowing blue smoke for about 5 or so minutes. Went away after that. Also at start up seems to be running rich but not roughly. I hecked the oil before departure and was full, afyer 400km it was down needing a little. The engine is a import replacement of 40-50k km. I have have car and engine for 2years without an issue or oil usage. Is this a tuning issue or more serious as i suspect. Perhaps a compression test. Any thoughts?

PCV valve, a cheap and likely suspect.

Yea well, put a n a new PCV valve in the little car. When fully warmed up, from a standing start gassed it fairly hard, full throttle. Blew a fair bit of blue smoke/ black smoke. Gonna give it a compression test 2moz. Doesn't look good. Anyone know what a healthy Nba 2000 1.8lt non vvc engine compression test should read?

Have you pulled the plugs and looked?

Blue smoke is usually a sign of burning oil, and the fact the level dropped after 400km would suggest same.

I'd pull the spark plugs and give them a clean, it's likely that if the PCV jammed and sent some oil into the cylinders that the plugs are covered in residue, which could cause a bit of smoke at startup.

I'd clean them (or replace them, it's $20 for a full set) and give the car a good run to clear it out.



A cheap and nasty way to check if the rings are ok is to pull the dipstick and give it a sniff, if the oil smells of fuel that's a sign of combustion gases etc getting past the rings.
It's not as failsafe as a compression check (do wet and dry) but it's a quick indicator.