Hello, I recently fixed my cluster via help from these forums and was hoping y'all can help me once again. As of a few days ago whenever I start up my jeep it seems to start fine. Sitting there without moving the vehicle it has its idling RPM slightly lower than 1000rpm. Everything seems to be working fine until I pull out and drive somewhere. Whenever I put the car in neutral (its a 5 speed standard) and roll to a stop the car goes to very very low RPM's and on several occasions it has even turned off completely. I'm not sure what could be causing this and after some googling I found that its possible the distributor cap is damaged/needs to be replaced. I was hoping to get another point of view from some more experienced jeep owners on here. Hopefully I described the issue well enough but if not just let me know and I can possibly provide some videos of this happening if needed.

 

I had a similar issue, and it seems to have gone away after some maintenance on the grounds in the engine bay. Hope that helps.

 

Does it ever do it while idling in the driveway? or only after driving and rolling in neutral to a stop?

 

Louie, there are a lot of things it could be, but refreshing your grounds is always a good thing. You'd be amazed at how many odd or difficult problems are just due to flaky grounds. Have you checked out cruiser54's tips? It's a great place to start.

 

only happens after rolling in neutral to a stop.


Also before this When my gauges weren’t working I redid all the grounds so I don’t believe that it’s the grounds again

 

Do the RPMs decrease and motor die even if you attempt to increase the RPMs using the accelerator pedal? Or does it only happen when your foot is off the gas pedal?

 

if I give it gas then it doesn’t die so when driving I’ve been holding the gas pedal down to make sure I don’t lose it, this is becoming a problem because I have to break with my left foot and I’m very unaccustomed to that

 

Make sure your intake manifold bolts haven't loosened up.

Clean your throttle body and IAC. Here's how:

CRUISER'S MOSTLY RENIX TIPS

THROTTLE BODY AND IAC CLEANING

OCTOBER 30, 2015 SALAD 20 COMMENTS EDIT
Originally by TJWalker of CherokeeForum & JeepForum



The Idle Air Control (IAC) is mounted on the back of the throttle body (front for ’87-’90).

The valve controls the idle speed of the engine by controlling the amount of air flowing through the air control passage. It consists of a stepper motor that moves a pintle shaped plunger in and out of the air control passage. When the valve plunger is retracted, the air control passage flows more air which raises the idle speed. When the valve plunger is extended, the air control passage flows less air which lowers the idle speed.

Over time and miles, the IAC can get carboned up which can have an adverse affect on idle quality. Cleaning the IAC may restore proper function and is an easy procedure to perform and good preventive maintenance so it is never a bad idea. This should be part of a normal tune-up procedure and whenever idle/stalling issues are present.

CLEANING THE JEEP 4.0 IDLE AIR CONTROL

1. Remove the air filter cover, associated hoses and the rubber boot that goes from the air filter cover to the throttle body. Remove the IAC with a Torx driver (2 bolts; one can be kind of hard to get to). On ’91 and later, it may be easier to just remove the whole throttle body. Be sure to use a new throttle body to manifold gasket when reinstalling.
2. “Gently” wiggle out the IAC from the throttle body. Gasket/O-ring on the IAC can be re-used if it is not damaged
3. Clean the IAC with a spray can of throttle body cleaner; inexpensive and available at any place that sells auto parts. Throttle body cleaner is recommended rather than carburetor cleaner as it is less harsh, safe for throttle body coatings and oxygen sensors. Use cleaner, a rag and a toothbrush and or Q-Tips. Be gentle; don’t twist or pull on the pintle that protrudes from the IAC as it is fragile and you could damage it.
4. Thoroughly spray clean and flush where the IAC seats in the throttle body with the same spray cleaner.
5. It is also a good idea to clean the entire throttle body bore itself, the butterfly valve inside of the throttle body and it’s edges, and all associated linkage as long as you have things disassembled.

 

Like said, grounds, and cleaning the throttle body and IAC. I once emtpied two cans of cleaner into one it was so crusty. Smooth as glass after that.