My 2004 Micra SR Auto is losing engine oil. There is a build up of pressure in the crankcase when the engine is running: when I switch off the engine and remove the dipstick there is a fairly strong release of pressure, the same with the oil filler cap. I can't locate the engine breather which (in the old days) was a simple pipe into the air filter housing. Should the crankcase be relatively pressure free?
The oil appears to be coming from the rear main oil seal that was changed some months back.