tburk

Hey all,

Gotta 98 4.0 that will idle fine aroung 800-900 rpm in park or N, but sometimes when I come to a stop and the rpm's drop to that range its starts running rough, or at take off it will start to hesitate or stumble. If it does not die and you get out of the throttle quick enough and feather the accelerator it will (most of the time) take off normally. This started out every once in a while, but has started to become more frequently. Several times over the past couple days its died and then I have to mess with the shifter and key to get it to even turn over and start. She starts fine, and throughout the rest of the rpm range and shifts up through the gears just fine.

I have sprayed the throttle body with carb cleaner but she still does it.

Any suggestions? CPS? TPS? Manifold Pressure sensor? I dont want to go out and spend a ton of money throwing parts at it so any of you that have seen this before that are willing to lend some advice would be appreciated.

Thanks,
Todd

ivie_2006

first simple thing to check is try running some carb cleaner threw it maybe clean up the fuel system a lil bit, its cheap and easy to do great place to start truly does sound like a fuel system issue, after fuel i would check the ignition system but more then likely the fuel system is the bedst starting place..

desertdog

I would look at your IAC (idle air control) and EGR valve. I have a similar issue with my '90, occasionally the idle falls and it almost dies. Chances are it's the idle servo. You can remove and clean it for starters. It's the thing next to your throttle position sensor. I am not really the expert, just repeating what I've learned.

desertdog

Just read your post again; if you have to mess with the shifter you might have a neutral switch problem. It's an auto?

tburk

thanks for your reply's.

Im certain its not the N switch. It starts normally just fine, only after it dies while in D do I have to play around with that to get it started again.

Any suggestions?