Well I had a really rough Idle, ran decent when in gear driving. I replaced the IACV stepper motor (with a grand cherokee one) and now my idle sits pretty smoothly around 750rpm (seems kinda low to me). Also, when I put it in drive and I dont touch the gas it will accelerate on its own, in a two hundred yard stretch I was doing about 20mph. Any idea what could cause this? I also noticed at idle it puffs a little bit of grey smoke.I cant really atest to whether or not it did this before because I recently got the vehicle so I dont know.Any help would be greatly appreciated...Btw, it is a 96 Disco 1 4.0 with 155k miles, 5kmiles/1 year since full head job on the engine.thanks,spencer[/align]

 

Clean your t/body and check for a large vacuum leak which could be causing this idle problem.

 

any specific areas to look for when looking for vaccum leaks? I sprayed carb cleaner around the butterfly valve where the intake hose attaches. Should I remove it from the vehicle completely and clean?


Thanks,
spencer

 

No, just make sure you get all the black guh wiped out of the t/body.
As for leaks, check all hoses for crack, leaks or a spungy feeling. When the engine is COLD, start it and spray car cleaner around the entire intake manifold seal area, if the idle increases, you found your leak.

 

thanks I will give that a shot and see what happens