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Seasoned Member


Joined: Oct 2012
Posts: 328
Likes: 5
From: Dominican Republic
Year: 1990
Model: Cherokee
Engine: inline 6
Although I did redo all of that tubing back when I first purchased the beast. I should have moved it then, because it seemed like a dumb place to install it.
Let me ask you this: When I engage the cruise control switch on the turn signal stalk, should a light come on anywhere on the dash?
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
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
I'm having some trouble with a laundry list of engine codes on my 2001. I was hoping someone could help me figure out where to start (I need to get it inspected):
P0130 - O2 sensor Bank 1 Sensor 1 Heater Relay Circuit
P0135 - O2 Sensor Heater Bank 1 Sensor 1
P0136 - O2 Sensor Bank 1 Sensor 2 Heater Relay Circuit
P0141 - O2 Sensor Heater Bank 1 Sensor 2
P0155 - Bank 2 Sensor 1 Oxygen Sensor Heater Malfunction
P0443 - Evap Emissions Canister Purge Solenoid Control Circuit
All codes are "pending" except the P0443
I do have a small exhaust leak at the joint where the manifold meets the exhaust pipe, also the retaining clip on one of my O2 sensors was broken off by the PO. I cleaned that connection and used some electrical take to hold it together tight (not sure if either of these would contribute to the codes). I also replaced one of my grounds (the main body ground from engine to firewall with a large cable instead of the strap (I didn't relocate the engine mount for it is still on that PITA bolt in the back of engine --where does everyone relocate it to?)
Another thing. The jeep was running great (especially for 235k miles). After reading the codes I cleared them. I started up and the jeep ran REALLY REALLY rough, I drove for about 1 minute, the. the CEL popped back on and instantly the jeep smoothed right out and drove like a charm again.
Sorry for the LONG explanation, I'm hoping it helps someone help me figure this out.
Thanks in advance!
P0130 - O2 sensor Bank 1 Sensor 1 Heater Relay Circuit
P0135 - O2 Sensor Heater Bank 1 Sensor 1
P0136 - O2 Sensor Bank 1 Sensor 2 Heater Relay Circuit
P0141 - O2 Sensor Heater Bank 1 Sensor 2
P0155 - Bank 2 Sensor 1 Oxygen Sensor Heater Malfunction
P0443 - Evap Emissions Canister Purge Solenoid Control Circuit
All codes are "pending" except the P0443
I do have a small exhaust leak at the joint where the manifold meets the exhaust pipe, also the retaining clip on one of my O2 sensors was broken off by the PO. I cleaned that connection and used some electrical take to hold it together tight (not sure if either of these would contribute to the codes). I also replaced one of my grounds (the main body ground from engine to firewall with a large cable instead of the strap (I didn't relocate the engine mount for it is still on that PITA bolt in the back of engine --where does everyone relocate it to?)
Another thing. The jeep was running great (especially for 235k miles). After reading the codes I cleared them. I started up and the jeep ran REALLY REALLY rough, I drove for about 1 minute, the. the CEL popped back on and instantly the jeep smoothed right out and drove like a charm again.
Sorry for the LONG explanation, I'm hoping it helps someone help me figure this out.
Thanks in advance!
CF Veteran

Joined: Feb 2015
Posts: 1,528
Likes: 2
From: North Carolina
Year: 1993
Model: Cherokee
Engine: 4.0
Hey, was looking over my engine the other day and checked the oil. I had just started it and it had been running for about 3-4 min. When I check the oil, I noticed some bubbles and it also smelled like gas. I just changed the oil about 200 miles ago. Is is normal? I mainly use the jeep for driving out in the field and back and just small stuff. So a lot of the times I'm just started it and driving it for 10 min and parking it. Any ideas?
Senior Member



Joined: Sep 2015
Posts: 939
Likes: 71
From: Abysmo, NJ
Year: 1999
Model: Cherokee
Engine: 4.0
Usually what you do in these conversions is flush the old oil out (though you don't flush the compressor, just drain it), put in new ester oil, replace the drier, install R134a fittings, then pull vacuum for a while and refill with the proper amount of R134a. That's a quick and dirty description and pretty much the minimum, your system may well need other repairs. Also be aware that R134a is less efficient than R12. On some vehicles this is more noticeable than others.
There are also some alternative refrigerants available that will more-or-less drop in and "just work" in an R12 system. However you would need to check local laws since some, such as Enviro-Safe, are flammable. Also in general no shop will touch a system with an alternative refrigerant installed, you would be committing to working on the system yourself.
Seasoned Member
Joined: Nov 2011
Posts: 291
Likes: 1
From: Snohomish County, WA
Year: 1989
Model: Cherokee
Engine: 4.0L
Also be aware that R134a is less efficient than R12. On some vehicles this is more noticeable than others.
There are also some alternative refrigerants available that will more-or-less drop in and "just work" in an R12 system. However you would need to check local laws since some, such as Enviro-Safe, are flammable. Also in general no shop will touch a system with an alternative refrigerant installed, you would be committing to working on the system yourself.
There are also some alternative refrigerants available that will more-or-less drop in and "just work" in an R12 system. However you would need to check local laws since some, such as Enviro-Safe, are flammable. Also in general no shop will touch a system with an alternative refrigerant installed, you would be committing to working on the system yourself.
No, I don't lick fish.



Joined: Mar 2011
Posts: 11,169
Likes: 26
From: Northern Kentucky
Year: 1999
Model: Cherokee (XJ)
Engine: 4.0
You may not need to change the compressor depending on condition. If you do get a new or rebuilt one it will be R134a compatible out of the box.
Usually what you do in these conversions is flush the old oil out (though you don't flush the compressor, just drain it), put in new ester oil, replace the drier, install R134a fittings, then pull vacuum for a while and refill with the proper amount of R134a. That's a quick and dirty description and pretty much the minimum, your system may well need other repairs. Also be aware that R134a is less efficient than R12. On some vehicles this is more noticeable than others.
There are also some alternative refrigerants available that will more-or-less drop in and "just work" in an R12 system. However you would need to check local laws since some, such as Enviro-Safe, are flammable. Also in general no shop will touch a system with an alternative refrigerant installed, you would be committing to working on the system yourself.
Usually what you do in these conversions is flush the old oil out (though you don't flush the compressor, just drain it), put in new ester oil, replace the drier, install R134a fittings, then pull vacuum for a while and refill with the proper amount of R134a. That's a quick and dirty description and pretty much the minimum, your system may well need other repairs. Also be aware that R134a is less efficient than R12. On some vehicles this is more noticeable than others.
There are also some alternative refrigerants available that will more-or-less drop in and "just work" in an R12 system. However you would need to check local laws since some, such as Enviro-Safe, are flammable. Also in general no shop will touch a system with an alternative refrigerant installed, you would be committing to working on the system yourself.
Thanks for the info! That helps.
Herp Derp Jerp

Joined: Nov 2011
Posts: 18,251
Likes: 17
From: Parham, ON
Year: 1999
Model: Cherokee
Engine: 4.0L OBD-II
Isn't that AC refill stuff in a can basically propane?
It's very possible that, since you don't let it get up to temperatur, residual fuel is never being evaporated. I find that gas engine oil will always smell like gasoline to a small degree. Excessive bubbles on the dip stick are troubling.
The possibility exists that you have a leaky injector. Go for a drive and get that thing hot for a while, then after letting it cool, If you let some drip onto your ungloved fingers does it run between your fingerprint ridges?
You could also get a fuel pressure gauge and see how long it takes to lose pressure.
(Similar thing can happen with water from not being allowed to get up to temp to boil off moisture)
Hey, was looking over my engine the other day and checked the oil. I had just started it and it had been running for about 3-4 min. When I check the oil, I noticed some bubbles and it also smelled like gas. I just changed the oil about 200 miles ago. Is is normal? I mainly use the jeep for driving out in the field and back and just small stuff. So a lot of the times I'm just started it and driving it for 10 min and parking it. Any ideas?
The possibility exists that you have a leaky injector. Go for a drive and get that thing hot for a while, then after letting it cool, If you let some drip onto your ungloved fingers does it run between your fingerprint ridges?
You could also get a fuel pressure gauge and see how long it takes to lose pressure.
(Similar thing can happen with water from not being allowed to get up to temp to boil off moisture)
Herp Derp Jerp

Joined: Nov 2011
Posts: 18,251
Likes: 17
From: Parham, ON
Year: 1999
Model: Cherokee
Engine: 4.0L OBD-II
Maybe. If they're the same transmission, the input gear will be the same and bolt up fine.
In 1996 they changed to a different output on the main shaft. Your 1994 has a tail cone with a seal on it that lets the slip yoke, er, slip in and out. It's lubricated by ATF. The 2000's transfer case is a closed unit and the slip yoke is greased and covered by a dust boot. As far as I'm aware the shafts aren't compatible (1994s having need to be machined to fit the seal properly), so if they also have the same rear axle, you can just swap the shafts over.
In 1996 they changed to a different output on the main shaft. Your 1994 has a tail cone with a seal on it that lets the slip yoke, er, slip in and out. It's lubricated by ATF. The 2000's transfer case is a closed unit and the slip yoke is greased and covered by a dust boot. As far as I'm aware the shafts aren't compatible (1994s having need to be machined to fit the seal properly), so if they also have the same rear axle, you can just swap the shafts over.
Seasoned Member
Joined: Dec 2013
Posts: 473
Likes: 0
From: SATX
Year: 1999
Model: Cherokee
Engine: 4.0 I6
So a couple weeks ago I installed an H4 conversion kit along with the upgraded headlight harness. Increased visibility is great but I notice that they dim at stops whenever E fan kicks on. A little research later, I've decided to upgrade the alternator.
I plan on running a winch, lights, etc in the future.
Is 160 amp too much? I'm pretty sure I have to upgrade wiring to battery and that's ok just don't wanna fry something.
I'm making a junkyard run. What am I looking for on the alt? ie. markings, specific connections? Pics would help tremendously. Thanks.
I plan on running a winch, lights, etc in the future.
Is 160 amp too much? I'm pretty sure I have to upgrade wiring to battery and that's ok just don't wanna fry something.
I'm making a junkyard run. What am I looking for on the alt? ie. markings, specific connections? Pics would help tremendously. Thanks.




