Hello,

My 91 Civic DX (1.5L, 195K miles) has been burning industrial amounts of oil (2 qts / 100 miles). After breaking a valve, I put in a lower mileage head from a junkyard, but made no difference in oil consumption. I plugged the PCV hose to see if it was sucking oil out of the crankcase into the intake, but no difference. I am wondering if I have a cracked piston ring somewhere. I checked compression and all four cylinders were at 175-195 psi. Here is a picture of the plugs.



It is obviously running very rich (plugs only have 300 miles) and #1 on the left looks pretty oily. I am thinking of pulling the head again, and pulling the pistons out to re-ring (the ridge on the cyls looked pretty minor).

What do you think?

Thanks,

Mikel

 

Flick the PCV, the valve inside should jiggle, and check for vacuum, if it has both then the PCV should be fine. The piston rings should be fine also since you have pretty good compression. Did you run a wet compression test?