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CF Veteran
Joined: Apr 2011
Posts: 14,553
Likes: 1
From: Carrollton, GA
Year: 1994
Model: Cherokee
Engine: Inline 6 4.0L High Output
Need longer LCA's unless your lift came with em... Caster wont move it that much i dont think
Member
Joined: Sep 2012
Posts: 148
Likes: 1
From: loma linda
Year: 90
Model: Cherokee
Engine: 4.0 with Bomb proof mounts
mabe springs need to seat? I can take pics tomarrow to dark now.
☠ CF Sheriff ☠

Joined: Nov 2009
Posts: 15,197
Likes: 18
From: Aberdeen, MD
Year: 1995
Model: Cherokee
Engine: 4.0L HO I-6, 703 Injectors, Brown Dog Super Engine Mounts
CF Veteran
Joined: Jan 2012
Posts: 8,272
Likes: 1
From: Baltimore, MD
Year: 1999
Model: Cherokee
Engine: 4.0 I6 HO
i have a small amount of driveline vibrations as stated before. my lift has settled a lot and they are way less. my rear u joint was a little mangled during the lift install and isnt seated right. if i get a new ujoint installed should i still need an SYE? or is this a try it and find out thing?
CF Veteran

Joined: Apr 2011
Posts: 3,493
Likes: 0
From: Chickamauga Ga.
Year: 2000
Model: Cherokee
Engine: 4.0
Originally Posted by dukie564
Looks good. Added some wire sizes for you. Those are the minimum sizes you need assuming the lights you have are all 55W lights.
CF Veteran

Joined: Apr 2011
Posts: 3,493
Likes: 0
From: Chickamauga Ga.
Year: 2000
Model: Cherokee
Engine: 4.0
Originally Posted by a_shirey
i have a small amount of driveline vibrations as stated before. my lift has settled a lot and they are way less. my rear u joint was a little mangled during the lift install and isnt seated right. if i get a new ujoint installed should i still need an SYE? or is this a try it and find out thing?
Member
Joined: Jun 2012
Posts: 138
Likes: 0
From: Central Frontenac, ON Canada
Year: 2001
Model: Cherokee
Engine: 4.0
I had my CEL come on a month ago and it was a P0303, misfire cylinder 3, I cleared the code and didn't really think anything of it. Jeep ran good, milegae was good, just a little rough on the idle but nothing to really speak of and the CEL didn't come back.
Then I got a new toy, bluetooth OBD reader, so now I can look at codes and the engine a little more real time on my computer and discovered that the engine is throwing the 03 misfire code all the time. I guess that it doesn't do it enough to trigger the CEL circuit, there must be some tolerance in the programming.
So I used the search function here and have a list of things to check and do;
Check wiring harness for breaks and grounding.
Change spark plugs, NGKs since I have an 01, gap .035. Anti seize and diaelectric grease.
Inspect boots and change if required.
Am I missing anything and is are there any gotchas that I should be careful about?
Thanks for the help!!
Then I got a new toy, bluetooth OBD reader, so now I can look at codes and the engine a little more real time on my computer and discovered that the engine is throwing the 03 misfire code all the time. I guess that it doesn't do it enough to trigger the CEL circuit, there must be some tolerance in the programming.
So I used the search function here and have a list of things to check and do;
Check wiring harness for breaks and grounding.
Change spark plugs, NGKs since I have an 01, gap .035. Anti seize and diaelectric grease.
Inspect boots and change if required.
Am I missing anything and is are there any gotchas that I should be careful about?
Thanks for the help!!
Senior Member
Joined: Jun 2012
Posts: 634
Likes: 0
From: Cuyahoga Falls
Year: 1994
Model: Cherokee
Engine: 4.0l
Originally Posted by Sails
I had my CEL come on a month ago and it was a P0303, misfire cylinder 3, I cleared the code and didn't really think anything of it. Jeep ran good, milegae was good, just a little rough on the idle but nothing to really speak of and the CEL didn't come back.
Then I got a new toy, bluetooth OBD reader, so now I can look at codes and the engine a little more real time on my computer and discovered that the engine is throwing the 03 misfire code all the time. I guess that it doesn't do it enough to trigger the CEL circuit, there must be some tolerance in the programming.
So I used the search function here and have a list of things to check and do;
Check wiring harness for breaks and grounding.
Change spark plugs, NGKs since I have an 01, gap .035. Anti seize and diaelectric grease.
Inspect boots and change if required.
Am I missing anything and is are there any gotchas that I should be careful about?
Thanks for the help!!
Then I got a new toy, bluetooth OBD reader, so now I can look at codes and the engine a little more real time on my computer and discovered that the engine is throwing the 03 misfire code all the time. I guess that it doesn't do it enough to trigger the CEL circuit, there must be some tolerance in the programming.
So I used the search function here and have a list of things to check and do;
Check wiring harness for breaks and grounding.
Change spark plugs, NGKs since I have an 01, gap .035. Anti seize and diaelectric grease.
Inspect boots and change if required.
Am I missing anything and is are there any gotchas that I should be careful about?
Thanks for the help!!
Herp Derp Jerp

Joined: Nov 2011
Posts: 18,251
Likes: 17
From: Parham, ON
Year: 1999
Model: Cherokee
Engine: 4.0L OBD-II
Sails, since you did plugs already, the next steps are to move the coil packs to other cylinders and see if the misfire follows. If not I'd dry fuel injectors as well. Then a compression test
Member
Joined: Jun 2012
Posts: 138
Likes: 0
From: Central Frontenac, ON Canada
Year: 2001
Model: Cherokee
Engine: 4.0
I will keep in mind your suggestion about moving the packs around if I don't find it with the plugs and wiring, excellent idea rather than throwing parts at it. Same with the injectors if it comes to that.
I am a little confused as to how a compression test or low compression would contribute to a misfire. I would think that the misfire code would relate to the pack/plug/wiring issue. I agree that low compression could lead to the roughish idle and lossy performance and lossy mileage neither of which I have.
Enlightenment would be appreciated!
Thanks and I wasn't really going to look for a cap & points ...
Herp Derp Jerp

Joined: Nov 2011
Posts: 18,251
Likes: 17
From: Parham, ON
Year: 1999
Model: Cherokee
Engine: 4.0L OBD-II
Actually I haven't done anything yet, I am hopeful that it will turn out to be a wiring rub and will change the plugs just because I should.
I will keep in mind your suggestion about moving the packs around if I don't find it with the plugs and wiring, excellent idea rather than throwing parts at it. Same with the injectors if it comes to that.
I am a little confused as to how a compression test or low compression would contribute to a misfire. I would think that the misfire code would relate to the pack/plug/wiring issue. I agree that low compression could lead to the roughish idle and lossy performance and lossy mileage neither of which I have.
Enlightenment would be appreciated!
Thanks and I wasn't really going to look for a cap & points ...
I will keep in mind your suggestion about moving the packs around if I don't find it with the plugs and wiring, excellent idea rather than throwing parts at it. Same with the injectors if it comes to that.
I am a little confused as to how a compression test or low compression would contribute to a misfire. I would think that the misfire code would relate to the pack/plug/wiring issue. I agree that low compression could lead to the roughish idle and lossy performance and lossy mileage neither of which I have.
Enlightenment would be appreciated!
Thanks and I wasn't really going to look for a cap & points ...
Regarding what throws a misfire code, there's another thread somewhere around here where that was discussed. Misfires are determined by reading the signal from the CPS. The ECU expects a certain amount of push every time a cylinder is fired, equating to an increase in the rotational speed of the flywheel. It measures the average of each cylinder and throws a code if it's uneven. Anything that causes a less powerful explosion in a cylinder will throw a code, like burnt valve, missing seals, lots of oil, bad rings, bad gas, no gas, too much gas, bad spark... blah blah blah
An additional question for you - any odd noises from the engine itself? I've been spending a lot of time reading about sticky lifters on the 4.0 which will result in the valves not opening properly
Senior Member
Joined: Jun 2012
Posts: 634
Likes: 0
From: Cuyahoga Falls
Year: 1994
Model: Cherokee
Engine: 4.0l
Yeah didn't know the o1 had cool packs, what yr did they switch over.
Also check plugs if that #3 cylinder looks diff then the others could have a mechanical issue
Also check plugs if that #3 cylinder looks diff then the others could have a mechanical issue




