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.

99 XJ 4.0 check engine light, almost died while driving.

Thread Tools
 
Search this Thread
 
Old 09-15-2011, 06:17 PM
  #1  
Member
Thread Starter
 
jowint's Avatar
 
Join Date: Jan 2011
Posts: 228
Likes: 0
Received 1 Like on 1 Post
Model: Cherokee
Default 99 XJ 4.0 check engine light, almost died while driving.

I was cruising about 65 mph on the highway smoothly when all of the sudden under light load the engine started sputtering badly and it almost died, but after a few flogs of the gas pedal it came back to life then did it once again briefly at the same speed and the check engine light came on- then it ran smooth all week long.
I thought I may have had a bad crankshaft position sensor but then I remembered that at times under off idle acceleration the engine would buck and skip until I gave it more gas which led me to believe the TPS was going bad.
I checked codes and found a TPS code.

Looks like I need a new TPS but I'm not sure if its the whole throttle body or not.

Any help would be appreciated.

If I do have to replace the throttle body are there any performance mods I could add while in there?
Old 09-15-2011, 06:20 PM
  #2  
Senior Member
 
Lyon's Avatar
 
Join Date: Jan 2011
Posts: 948
Likes: 0
Received 1 Like on 1 Post
Default

It's not common that the throttle body actually goes bad. Most likely it is just the TPS. I believe you need a T-15 torx tip to remove it iirc. It's only 2 screws. They run about $40 new at Advance or Auto Zone.
Old 09-15-2011, 06:22 PM
  #3  
Member
Thread Starter
 
jowint's Avatar
 
Join Date: Jan 2011
Posts: 228
Likes: 0
Received 1 Like on 1 Post
Model: Cherokee
Default

Originally Posted by Lyon
It's not common that the throttle body actually goes bad. Most likely it is just the TPS. I believe you need a T-15 torx tip to remove it iirc. It's only 2 screws. They run about $40 new at Advance or Auto Zone.
Cool, thx.
Old 09-16-2011, 10:39 AM
  #4  
Member
Thread Starter
 
jowint's Avatar
 
Join Date: Jan 2011
Posts: 228
Likes: 0
Received 1 Like on 1 Post
Model: Cherokee
Default

I replaced the TPS today.

The T-20 torx were pretty tight and I thought for sure I was gonna strip the bolt holes but I bent 2 cheap torx bits trying to get it out until I broke out my good, hardened bits.
Looks like they put them in with loc-tite.

Anyways the install went fine and it runs great so far, BUT....I noticed that the vehicle idles high now at about 1100 rpm even after the test drive.

Is there anything I can do to get the idle to come down a bit?
Old 09-16-2011, 03:12 PM
  #5  
Member
Thread Starter
 
jowint's Avatar
 
Join Date: Jan 2011
Posts: 228
Likes: 0
Received 1 Like on 1 Post
Model: Cherokee
Default

Bump, any ideas on 1100 rpm idle after TPS replacement?
Old 09-18-2011, 09:16 AM
  #6  
Junior Member
 
defconOne's Avatar
 
Join Date: May 2010
Location: Singapore
Posts: 94
Likes: 0
Received 1 Like on 1 Post
Year: 1996
Model: Cherokee
Engine: 4.0
Default

Have u reset your ECU after changing new TPS?
Old 09-18-2011, 09:57 AM
  #7  
Senior Member
 
kyledye25's Avatar
 
Join Date: Feb 2011
Location: Apollo, PA
Posts: 517
Likes: 0
Received 0 Likes on 0 Posts
Year: 1996
Model: Cherokee
Engine: 4.0
Default

Sorry to high jack...but where would be the best place to buy a tps sensor? I think I am in need of one. Mopar? Anyone have good luck with other kinds oust then Mopar. Most of the time I buy Mopar. Just curious if there's a cheaper one out there that's just as good or better. Thanks.
Old 09-18-2011, 10:27 AM
  #8  
Senior Member
 
bigvig's Avatar
 
Join Date: Nov 2009
Location: Maine
Posts: 904
Received 3 Likes on 3 Posts
Year: 1999 Sport
Model: Cherokee
Engine: I6
Default

Same thing happen to me a few years ago. On the highway doing 75 and she started spitting and bucking every mile like clockwork. Came down to 65 and it corrected some of it but I had about 10 miles to go. Stuck it out and made it. Sears checked the code, it was the TPS and I picked up a new one at NAPA for $40ish. Swapped it out, didnt reset the computer and had no issues after. This was 3 1/2 years ago now and still running strong.
Old 09-18-2011, 10:58 AM
  #9  
CF Veteran
 
VTJeep's Avatar
 
Join Date: Jul 2010
Location: 802
Posts: 4,930
Likes: 0
Received 3 Likes on 3 Posts
Year: 99
Model: Cherokee
Engine: 4.0
Default

you dont reset computer.
a new TPS should be 40 ish
if its idling high, it could be the IAC valve. is CEL still on? or have codes been cleared?
Old 09-18-2011, 12:53 PM
  #10  
Member
Thread Starter
 
jowint's Avatar
 
Join Date: Jan 2011
Posts: 228
Likes: 0
Received 1 Like on 1 Post
Model: Cherokee
Default

Ok fella's.

I did clear the codes before replacing the sensor.
I test drove it once and had the high idle so I thought maybe the computer would relearn the new sensor after driving a while or a couple more key cycles.

Well I took the jeep to my hunting spot in blue ridge this weekend and it did fine on my initial start up out of my buddy's driveway after I picked him up so I guess it relearned what it needed to....all is well and the rpm is now normal.

Just for kicks.....what is the procedure for relearning the ECU?
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
clark40
Modified XJ Cherokee Tech
7
08-28-2015 03:08 PM
03cheroke
Stock Grand Cherokee Tech. All ZJ/WJ/WK Non-modified/stock questions go here!
2
08-27-2015 06:07 AM
Kevin Icenhour
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
2
08-21-2015 08:22 PM
CCKen
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
3
08-20-2015 08:07 PM
cbowl
Cherokee Chat
2
08-19-2015 09:14 PM

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


Quick Reply: 99 XJ 4.0 check engine light, almost died while driving.



All times are GMT -5. The time now is 04:58 AM.