I just bought a 2001 dodge ram 1500 5.2l 5spd. Its wants to Idle at 3000rpm when the truck is rolling and the clutch is disengaged. If the truck is stopped it idles down to about 600 rpm. The service engine soon light come on for a while and goes off again, I haven't had a chance to put a code reader on it yet.

Best answer to the first who gives the correct diagnosis.