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.

93xj running to rich and bad gas milage

Thread Tools
 
Search this Thread
 
Old 03-07-2009, 09:34 PM
  #1  
Seasoned Member
Thread Starter
 
lifted93xj's Avatar
 
Join Date: Dec 2008
Posts: 352
Likes: 0
Received 0 Likes on 0 Posts
Year: 1993
Model: Cherokee
Engine: 4.0L
Default 93xj running to rich and bad gas milage

So i just did a complete tune-up on my cherokee. New plugs, wires, cap/rotor, fuel filter, o2 sensor, map sensor, fuel pressure regulator, seafoam, also cleaned throttle body and iac sensor.

Now it still idles bad(sounds like its spitting), get about 11.5mpg, and also exhuast smells like gas.

HELP PLEASE.
Old 03-08-2009, 12:24 AM
  #2  
Seasoned Member
Thread Starter
 
lifted93xj's Avatar
 
Join Date: Dec 2008
Posts: 352
Likes: 0
Received 0 Likes on 0 Posts
Year: 1993
Model: Cherokee
Engine: 4.0L
Default

help please
Old 03-08-2009, 01:46 AM
  #3  
Newbie
 
4x4tirechirp's Avatar
 
Join Date: Mar 2009
Posts: 20
Likes: 0
Received 0 Likes on 0 Posts
Year: 1993
Model: Cherokee
Engine: 4.0L I6 MPI "Power Tech HO"
Default Hmmmmmm. . . .

cylinder compression? Just wondering, that happened to my friend's dodge. He had to put in new piston rings. If some of the gass smell goes away when the engine is hot then it could be the rings are too worn and they are just making a better seal when they expand when it is hot. just a tentative thought though.

injectors?

Last edited by 4x4tirechirp; 03-08-2009 at 01:48 AM.
Old 03-08-2009, 10:22 AM
  #4  
Seasoned Member
Thread Starter
 
lifted93xj's Avatar
 
Join Date: Dec 2008
Posts: 352
Likes: 0
Received 0 Likes on 0 Posts
Year: 1993
Model: Cherokee
Engine: 4.0L
Default

not leaking oil on the spark plugs and not blowin any blue smoke.
Old 03-08-2009, 10:33 AM
  #5  
CF Veteran
 
OverlandZJ's Avatar
 
Join Date: May 2008
Location: Bristol,Pa
Posts: 5,188
Likes: 0
Received 6 Likes on 6 Posts
Year: 94
Model: Cherokee
Engine: 4.0L
Default

Does it feel like it has a loss of power? Cat could have broken up and have a partial clog.

I recently had the same issue.
Old 03-08-2009, 11:46 AM
  #6  
CF Veteran
 
Howler_GT's Avatar
 
Join Date: Jul 2008
Location: Schnecksville, PA
Posts: 1,217
Likes: 0
Received 5 Likes on 5 Posts
Year: 94 XJ
Model: Cherokee
Engine: 4.0L
Default

Change air cleaner and then clean your IAT sensor.

Use this for reference:

https://www.cherokeeforum.com/f51/budget-airbox-mod-iat-relocation-2599/

Have you changed your thermostat?
Is it a 190* or have you made the same mistake as others and switched to a 180*?
Old 03-08-2009, 02:55 PM
  #7  
Seasoned Member
Thread Starter
 
lifted93xj's Avatar
 
Join Date: Dec 2008
Posts: 352
Likes: 0
Received 0 Likes on 0 Posts
Year: 1993
Model: Cherokee
Engine: 4.0L
Default

Cat is aftermarket high flow and i just bought a k&n intake system
Old 03-08-2009, 02:58 PM
  #8  
Seasoned Member
Thread Starter
 
lifted93xj's Avatar
 
Join Date: Dec 2008
Posts: 352
Likes: 0
Received 0 Likes on 0 Posts
Year: 1993
Model: Cherokee
Engine: 4.0L
Default

i havent changed the thermostat out.
Old 03-10-2009, 01:19 AM
  #9  
Newbie
 
4x4tirechirp's Avatar
 
Join Date: Mar 2009
Posts: 20
Likes: 0
Received 0 Likes on 0 Posts
Year: 1993
Model: Cherokee
Engine: 4.0L I6 MPI "Power Tech HO"
Default try these things

intake air temp. sensor= check; Upstream O2 sensor replacement (this is most likely only the cause if it runs at a higher rpm for the first 2-5 minutes of idle); very unlikely but try testing the idle control motor or the idle control valve---one last thing the manifold absoulut pressure sensor or the MAP sensor. you could try to see if the problem abates if you reboot the ECU by disconecting the battery too. (however i really don't like this meathod of "fixing" problems 'cause it erases the error codes that have been stored)
just a few thoughts again.
Old 03-10-2009, 06:08 PM
  #10  
Seasoned Member
Thread Starter
 
lifted93xj's Avatar
 
Join Date: Dec 2008
Posts: 352
Likes: 0
Received 0 Likes on 0 Posts
Year: 1993
Model: Cherokee
Engine: 4.0L
Default

thanks again. i replaced the o2 sensor and the map.
Old 01-30-2012, 07:05 PM
  #11  
Newbie
 
Aussie Mike's Avatar
 
Join Date: Jan 2012
Posts: 12
Likes: 0
Received 0 Likes on 0 Posts
Model: Cherokee
Default

Similar problems, did the Map and o2 senser fix it for you?
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Motorbreath8579
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
4
07-07-2016 12:29 PM
95cherokee89
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
59
10-16-2015 03:17 AM
Ye Ol' Cherokee
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
15
09-05-2015 04:36 PM
jghaenlein
Stock Grand Cherokee Tech. All ZJ/WJ/WK Non-modified/stock questions go here!
8
08-27-2015 07:07 AM
Tom95YJ
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
4
08-21-2015 06:20 PM

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


Quick Reply: 93xj running to rich and bad gas milage



All times are GMT -5. The time now is 04:35 AM.