I have a 2002 Mitsubishi Eclipse GT, V-6, 5-speed manual transmission.
84,000 miles, the oil is changed every 3,000 miles and the car is generally
well maintained. I always fill it with premium fuel. I don't hot rod the car
although I do take advantage of the extra power and handling from time to
time on the freeway.

About three months ago, I started the car and headed off to work. At the end
of our street, about one-third of a mile, I stopped at the stop sign. The
road is inclined slightly uphill at that point. The idle suddenly got very
rough and the tach jumped between 600 and 900 as I sat there. Also, the
"Check Engine Soon" light went on. I headed out onto the main road, driving
several miles at 40-45 MPH. At the first stop light, the idle had smoothed
out but the check light stayed on. There was no further problem with the
idle and the check light went out the next afternoon.

The car ran without incident until this Monday, when the same process
repeated. Rough idle at the first stop in the morning, check light goes on,
no more idle problems, check light goes off the next afternoon.

Any ideas about what could be causing this? I don't want to take it into the
shop unless I need to but I don't want this infrequent, minor problem to
lead to something serious.

Thanks for any answers,

Paul