Well, I've done some smoke-searching on the forums, but couldn't really find anything helpful on this particular issue. After I drive for 20 minutes or more, I get thin blue-grayish smoke with an oily smell seeping through the right headlight cover. It seems to be coming from underneath the engine/radiator area for a few more minutes after I stop. I assume that's oil leaking onto the hot exhaust somewhere. Is this a serious problem, and is it hard to find and fix? My oil consumption isn't noticeably higher than usual. The car is a 1990 non-turbo convertible with a little over 160k miles on it, and I pour a cheap 10W40 semi-synthetic. Also, the "check engine" light comes on when I turn on the electrics, but goes off once I start the engine.

Thanks in advance for any guidance.

 

Sounds like a metering oil line may be leaking. Degrease the engine bay, go for a short drive, and then look for the leak around the bottom left of the front of the engine.

The lines themselves are cheap but the upper intake needs to come off to access them.