CEL
Same thing with my '93 here...but I know what causes mine. I found after using several exhausts how sensitive those sensors can be. It seems to be something along the lines of exhaust flow/backpressure...staying in gear with low rpms, driving up hills as speed decreases (steep incline), even letting off the gas suddenly but not pushing the clutch, etc. seem to be the factor in my CEL coming on once in awhile. Normal driving and getting the flow going again usually makes it go away.
There have been a few times when it just lights up on the highway or something, but even if it stays on for a half hour, it always goes off.
It is important to remember the CEL just means a sensor has gone out of its specified range...it's quite likely on older models things go out of range every so often, nothing to get worked up about...but it is worth it to get a code reader so you can hook it up and be sure nothing serious is causing your CEL, especially if it stays on for long periods of time or you can tell theres a mechanical problem.