My car idles from about 400 rpm to 1000rpm and just keeps rising and falling between those ranges. It will idle fine for about a minute or so and then starts doing it. It also almost cuts off after I start it when it has been started after it has been run. Any ideas? I was thinking maybe Idle/Air Control. THanks.



Patrick

 

what mods do you have on your stang kornfan?

 

I would check the IAC first. unplug it and see what happens

 

The car is completely stock.

 

i had that same problem in an 88 gt. we simply just cleaned out the throttle body were the butterfly is. sometimes you will find a lot of build up there. also don't forget the tubing in the cold air kit

 

Sounds like a vacuum leak. Check all the lines going into the intake, the FP Reg., line running from the smog pump, etc. . .

 

if nothing changes when you unplug the iac, spray carb cleaner on the vaccum lines one at a time and see if the idle surges

 

MY idle sticks at about 1500 for a second then drops to 1000 for a for a couple seconds then drops to normal, and i cant seem to find the problem,I heard to do something with an oimes meter have any ideas?

 

it's most likely in the dist....

 

ive seen a few things to cause this. first is the IAC, then the throttle position sensor, or maybe the map sensor. then you have vaccum leaks and so on.