I have a similar problem on my 3.2L SOHC Trooper, but it is intermittent as to when it will rear it's head. When it is a problem, the tach will read several hundred rpm low at idle, and several hundred rpm high at speed. I decided that it wasn't worth it...nothing is actually wrong with the engine or transmission, so I might aswell just leave it alone. Best o luck <img src="/forums/images/graemlins/smile.gif" alt="" />