I've got a bone stock 98 Cobra with 36k miles. After driving in traffic for a period of time, it will idle at 1200-1600RPM's. If you shut it off and instantly restart it, it will idle normally for a while. It doesn't do this every day and *seems* to happen more oftenwhen it's warmer and more humid outside (NE Ohio conditions) or if I take off and have the engine speed lower than where it might idle at.

Also sometimes right before it acts up, the idle speed will start wandering from about 800 RPMs to 1200RPMS beforegoingto the high idle. No check engine light. Other than that, the car runs totally fine. Is this a bad Idle Air Solenoid?

Thanks in advance!

i hav a 97 cobra and i live in ohio(weirdest weather pattern in America) but it sounds like it could need a Throttle Postion Sensor.

Had the same issue with my '01. TPS did the trick. It is easy to replace yourself.