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.

87 Jeep xj bucks and backfires only when warm

Thread Tools
 
Search this Thread
 
Old 05-19-2019, 09:15 PM
  #1  
Newbie
Thread Starter
 
Gogonerd15's Avatar
 
Join Date: May 2019
Posts: 3
Likes: 0
Received 0 Likes on 0 Posts
Model: Cherokee (XJ)
Default 87 Jeep xj bucks and backfires only when warm

I have a 1987 jeep xj with the 4.0 I6 and when I bought it, it's been having a problem. It will start up and drive fine, but after it gets warm it will buck, stutter, hesitate, backfire through the exhaust, and misfire but it wont shut off. The plugs will gas foul after a while like that. I've replaced the fuel filter, fuel pump, injectors, cleaned the tank, changed oil twice, redid plugs and wires, checked engine and gas compression, both good. Found one bad 02sensor, fixed it but that didn't help. Redid all the exhaust from drop pipe on. Replaced the map sensor, cleaned the throttle body, have a feeling the thermostat is out and it may be overheating, but dont know for sure. Please help! This problem wont go away and would love any ideas
Old 05-19-2019, 10:31 PM
  #2  
CF Veteran
 
tech's Avatar
 
Join Date: Jun 2016
Location: Santa Clarita California
Posts: 2,138
Likes: 0
Received 278 Likes on 244 Posts
Year: 2001
Model: Cherokee (XJ)
Engine: 4.0L
Default

You can try changing the coil I've seen them go bad that way , they will start losing spark when hot .
Old 05-20-2019, 08:16 AM
  #3  
::CF Moderator::
 
cruiser54's Avatar
 
Join Date: Aug 2011
Location: Prescott, Az
Posts: 43,971
Received 1,559 Likes on 1,263 Posts
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Default

Go to www.cruiser54.com and complete Tips 1 through 5 before doing anything else.

No cap and rotor replacement?
Old 05-20-2019, 05:02 PM
  #4  
Newbie
Thread Starter
 
Gogonerd15's Avatar
 
Join Date: May 2019
Posts: 3
Likes: 0
Received 0 Likes on 0 Posts
Model: Cherokee (XJ)
Default

Originally Posted by tech
You can try changing the coil I've seen them go bad that way , they will start losing spark when hot .
I took it to a shop, they said the distributor had oil in it, and that the harmonic balancer was off, would this cause my problem? How do you test a coil?

Last edited by Gogonerd15; 05-20-2019 at 05:07 PM.
Old 05-20-2019, 05:05 PM
  #5  
Newbie
Thread Starter
 
Gogonerd15's Avatar
 
Join Date: May 2019
Posts: 3
Likes: 0
Received 0 Likes on 0 Posts
Model: Cherokee (XJ)
Default

Originally Posted by cruiser54
Go to www.cruiser54.com and complete Tips 1 through 5 before doing anything else.

No cap and rotor replacement?
We have done cap but not rotor
Old 05-20-2019, 09:11 PM
  #6  
::CF Moderator::
 
cruiser54's Avatar
 
Join Date: Aug 2011
Location: Prescott, Az
Posts: 43,971
Received 1,559 Likes on 1,263 Posts
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Default

When you get it back, do the Tips.
Harmonic balancer will not affect running.

Make sure the shop does tip 13 when installing the distributor.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Redwolf624
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
3
02-26-2018 05:11 PM
1993grand
Stock Grand Cherokee Tech. All ZJ/WJ/WK Non-modified/stock questions go here!
1
12-26-2015 10:15 PM
hypedonmonster
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
82
04-29-2012 01:06 AM
cherokee90
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
3
06-11-2011 11:49 PM

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


Quick Reply: 87 Jeep xj bucks and backfires only when warm



All times are GMT -5. The time now is 06:18 PM.