’94 850 N/A with 105,000 miles.

I don’t know what to think about this engine. It’s got a slightly lumpy idle and miss at low RPM pulling, say at 2000 RPM and pulling a hill. It also burns about a quart of oil every 500 miles. No real leaks, a few seeps around the cam sensor and distributor, but nothing major. Several months ago I checked compression. I know had one cylinder with low compression, about 120 PSI in #5 AFAIR. A teaspoon of oil helped. Vacuum was good with a steady needle, so it seemed the rings in #5 were worn/broken/or scored cylinder. No codes.

Today I changed oil and checked compression again. Compression today was
165/168/171/180/165 hot. A teaspoon of oil raised them all by about 5 PSI. Vacuum is still a steady needle at 18" idle, 20" at 2000 rpm. WOT, the vacuum dropped to 0, and recovered to 23“. Plugs looked good, two maybe a bit lean, but none with oil fouling. I've still got a slightly lumpy idle, and still burn a quart every 500 miles. No leaks, but the seeps remain. No oil on a piece of cardboard under the engine overnight, after running the prior day. PCV hoses and oil trap were done about 5000 miles ago. Flame arrestor has been removed. How's the oil getting burned? Why do I have a lumpy idle? Plug wires are only about 2 years old, as is the dizzy cap and rotor. No carbon tracking in the cap or on the rotor. Plugs are Volvo branded, no excessive wear. Still no codes.

Any ideas?