I have a 1998 Integra LS with about 95,000 miles on it. Within the last two weeks I noticed a slight burning smell (kind of like burning rubber) when I'm idling at a stoplight after the engine has fully warmed up. I don't notice it when driving, only after I've stopped.

Yesterday after driving around for a while I parked and popped the hood and noticed a faint trace of smoke coming from underneath the engine block (near the dipstick). The car sounds and runs fine except for this problem.

I recently had the 90,000 mile service done (about a month ago) and I've never had a problem with the car. Any ideas what might be causing this?