Idle runs up and down at starting
 

Hi,
when I start my 1999 4x4 , 4.0, the engine IDLE sometime goes up and down (500rpm to 1500 Rpm) in cycle for at least 30 seconds becaming usually stable after that. In addition when the truck is running and coming to a stop, the idle takes a while to come down to a 700-1000 RPM range and stays high for a while. In general it sounds to me that the RPM is a bit high. It started doing that in the last couple of weeks....before that it used to be running fine. Any suggestion on the cause of the problem?

Re: Idle runs up and down at starting
 

had the same problem in my honda accord i think i might have been the pcv valve but could be wrong