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XJ Ask the Question Thread
CF Veteran

Joined: Apr 2011
Posts: 3,493
Likes: 0
From: Chickamauga Ga.
Year: 2000
Model: Cherokee
Engine: 4.0
Senior Member
Joined: Aug 2012
Posts: 583
Likes: 0
From: Clear Lake, TX
Year: 1999 Jeep Cherokee
Model: Cherokee
Engine: 4.0
So, new head, headers, new valves. Pulled the plugs today because my MPG is has been really bad the last few tanks. Was around 15ish now 12.5 to 13 mpg. The reworked head has about 900 to 1000 miles on it.
What is up with 3? 4 had a little black but nothing like 3. I replaced the E3s with some Champions today also.
So, what is causing this?
BTW, the 4.0 runs fine. No hesitation or rough idle.
What is up with 3? 4 had a little black but nothing like 3. I replaced the E3s with some Champions today also.
So, what is causing this?
BTW, the 4.0 runs fine. No hesitation or rough idle.
CF Veteran

Joined: Apr 2011
Posts: 3,493
Likes: 0
From: Chickamauga Ga.
Year: 2000
Model: Cherokee
Engine: 4.0
Senior Member
Joined: Apr 2012
Posts: 638
Likes: 0
From: Huntsville, Tn
Year: Different Years (I have several XJ's)
Model: Cherokee
Engine: 4.0 HO
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
Likes: 1,578
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
So, new head, headers, new valves. Pulled the plugs today because my MPG is has been really bad the last few tanks. Was around 15ish now 12.5 to 13 mpg. The reworked head has about 900 to 1000 miles on it.
What is up with 3? 4 had a little black but nothing like 3. I replaced the E3s with some Champions today also.
So, what is causing this?
BTW, the 4.0 runs fine. No hesitation or rough idle.
What is up with 3? 4 had a little black but nothing like 3. I replaced the E3s with some Champions today also.
So, what is causing this?
BTW, the 4.0 runs fine. No hesitation or rough idle.
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
Likes: 1,578
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
hello...Vag.com diagnostic woarks on jeep cherokee? i whant to check my injection pump diesel and i know this software does that but im not sure if will woark there . I know there are other diagnostic tools to jeep cherokee but my intencion is just check the injection pump valors and i think others diagnostic tools doesnt woark on that ..thankx
::CF Moderator::
Joined: Aug 2011
Posts: 43,971
Likes: 1,578
From: Prescott, Az
Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Senior Member
Joined: Apr 2012
Posts: 638
Likes: 0
From: Huntsville, Tn
Year: Different Years (I have several XJ's)
Model: Cherokee
Engine: 4.0 HO
Moderator of Jeeps
Joined: Jul 2011
Posts: 21,029
Likes: 3
From: Frederick, MD from Cleveland, OH
Year: 1993 YJ Wrangler
Engine: 4.0 I6
Sadly, his posts are more easily understood than some of the Americans'.





