Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here XJ (84-01)
All OEM related XJ specific tech. Examples, no start, general maintenance or anything that's stock.

RPMS drop to zero when stopped and engine dies

Thread Tools
 
Search this Thread
 
Old 03-17-2011, 09:48 AM
  #1  
Newbie
Thread Starter
 
SaraJo's Avatar
 
Join Date: Mar 2011
Location: Shepherdsville, KY
Posts: 22
Likes: 0
Received 0 Likes on 0 Posts
Year: 1995
Model: Cherokee
Engine: 4.0
Default RPMS drop to zero when stopped and engine dies

I have an automatic 95 cherokee sport. When I stop, my rpms drop to zero and my engine dies but everything else stays on. So when i come to a complete stop, i put the jeep in neutral and leave my foot on the gas to keep my rpms up and to keep my jeep from dieing. Now, when i am driving and i let my foot off the gas, the rpms drop to about 300 or less no matter what speed I am going. What could be wrong with the jeep?
Old 03-17-2011, 09:56 AM
  #2  
Junior Member
 
lfhoward's Avatar
 
Join Date: Apr 2010
Location: PA
Posts: 93
Likes: 0
Received 0 Likes on 0 Posts
Year: 2000
Model: Cherokee
Engine: 4.0L I6
Default

I had something similar happen to mine last year, where I couldn't get the engine to remain on without holding down the gas pedal slightly. Short term fix was to rev it really high for about a minute, but the problem came back after a few days. Turns out I had a dirty IAC (idle air control). I took that off the throttle body and cleaned it very carefully with throttle body cleaner and a toothbrush. The carbon build up was bad, but after I cleaned it (and the throttle body while I had it apart) I have had no further issues. Just be careful when you clean the IAC because it's pretty fragile. Don't twist it when you clean it (you'll see what I mean when you get it off). There are some good threads about cleaning the IAC on here that gave me the background to do it myself. You can probably do it in 30-60 minutes, or faster if you're used to working on your engine.
Old 03-17-2011, 05:16 PM
  #3  
CF Veteran
 
tjwalker's Avatar
 
Join Date: Nov 2010
Location: In the middle of Minnesota!
Posts: 5,804
Received 99 Likes on 88 Posts
Year: 1999
Model: Cherokee
Engine: 4.0
Default

Suspects:

1. Marginal battery (can absolutely create stalling/dying). Have it LOAD TESTED at any parts store for free

2. Idle air control and throttle body dirty or IAC faulty

3. Throttle position sensor

----------------------------------------------------------


The Idle Air Control (IAC) is mounted on the back of the throttle body. 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 moved in, the air control passage flows more air which raises the idle speed. When the valve plunger is moved out, 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.

CLEANING THE JEEP 4.0 IDLE AIR CONTROL

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)

“Gently” wiggle out the IAC from the throttle body. Gasket on the IAC can be re-used if it is not damaged

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 is best for this task. 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.

Thoroughly spray clean and flush where the IAC seats in the throttle body with the same spray cleaner

It is also a good idea to clean the entire throttle body itself, the butterfly valve inside of the throttle body and all associated linkage as long as you have things disassembled

Reinstall IAC and check idle quality
Old 03-17-2011, 05:18 PM
  #4  
CF Veteran
 
N20jeep's Avatar
 
Join Date: Mar 2010
Location: Jacksonville, FL
Posts: 6,685
Likes: 0
Received 5 Likes on 5 Posts
Year: 92
Model: Cherokee
Engine: 4.0
Default

Iac
Old 03-17-2011, 05:21 PM
  #5  
CF Veteran
 
freegdr's Avatar
 
Join Date: Mar 2010
Location: Broward County Fl.
Posts: 47,923
Likes: 0
Received 22 Likes on 22 Posts
Year: 1989 xj sport 2dr
Model: Cherokee
Engine: 12 hole bosch Injectors
Default

Originally Posted by N20jeep
Iac
x2 start here
Old 01-31-2013, 10:59 AM
  #6  
Newbie
Thread Starter
 
SaraJo's Avatar
 
Join Date: Mar 2011
Location: Shepherdsville, KY
Posts: 22
Likes: 0
Received 0 Likes on 0 Posts
Year: 1995
Model: Cherokee
Engine: 4.0
Default

I had fixed the problem with my 95xj. I took off the IAC and cleaned it and cleaned the throttle body. Never happened again

Last edited by SaraJo; 01-31-2013 at 12:05 PM.
Old 01-31-2013, 11:34 AM
  #7  
Junior Member
 
Kerry6363's Avatar
 
Join Date: Oct 2012
Posts: 39
Likes: 0
Received 0 Likes on 0 Posts
Model: Cherokee
Default

Make sure you have not damaged the iac o-ring when reinstalling, ask me how I know!
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Blackcherokee290
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
27
07-26-2022 07:52 PM
XJ ONLY
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
8
01-26-2019 06:30 PM
Ye Ol' Cherokee
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
3
04-25-2017 08:35 AM
Gtrsrlly
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
5
08-25-2015 11:50 AM
Kevin Icenhour
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
2
08-21-2015 08:22 PM

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 


Quick Reply: RPMS drop to zero when stopped and engine dies



All times are GMT -5. The time now is 07:52 AM.