2000 Cherokee Sport / 4.0 L / Auto XMSN / 4 x 4 / 227k mi / Orig from NJ
I have had this Jeep for about six months. In the beginning I experienced a minor sputter every once in a while which I attributed to dirty fuel as it had been sitting a few months. I ran clean gas and a bottle of quality Sea foam fuel cleaner / additive. Obviously, that didn't fix it.
Early on, the problem could be described as an occasional sputtering, chugging, but without any popping or back firing. It normally lasted only a few minutes then went back to purring like a kitten with plenty of power on it's own. The check engine light also blinks during the sputtering period.
While I normally get 18 mpg, as the occurrence of the sputtering problem frequency increased, the mileage sometimes drops to 12 mpg...
More recently, the problem occurred like clockwork when I shut it off to fill up and restarted. It lasted only long enough for me to idle through the parking lot and stopped as I got back on the road. Thinking it may have something to do with the old, cruddy, fuel cap, I replaced it with the recommended unit from Auto Zone.
While there I had them read the codes. Nothing jumped out at me, but they mentioned (from memory) a random misfire on cyl #3, some sort of fuel line issue (vacuum issue?), etc.
I then checked all vacuum lines and fixed a couple of minor leaks due to deteriorated lines / fittings.
I should mention that the exhaust was rotted off from the Cat back when I got it and I replaced the rotted items with a turbo muffler, and a tailpipe. The problem was no different before / after.
Most recently, as the malfunction frequency continued to increase, and NOT go away on its own but rather continue as you drive, the following occurred....
I drove it on the highway for approx 40 miles. All ok. Oil pressure always reads max. Water temp was normal at 200*. Upon reaching my destination, I noted a bit more engine / valve-train noise than usual.
After it sat for several hours, I started it and the popping, pulsing through the gas pedal, back firing at an idle started (first time ever).
I checked the oil which was still clean and at the proper level, but I observed (first occurrence) nasty, flakey, carbon flakes on the dipstick above the oil level.
Having no other choice, I drove it home.
The backfiring stopped just above idle. It sputtered during acceleration, however once at speed, it smoothed out, but had a noticeable reduction in power. It ran ok at a steady 60-70 mph, but was weak going up hills.
Since then I checked the oil again – proper level, clean, and with no water. The coolant level was a bit below the proper level but not milky either.
The popping is really bad and I have stopped running it until I can figure out what is happening.
I thank you all in advance for your help.
Merry Christmas!
Rick
https://onedrive.live.com/?cid=9EF666F89D644D14&id=9EF666F89D644D14%213293&v=3
I have had this Jeep for about six months. In the beginning I experienced a minor sputter every once in a while which I attributed to dirty fuel as it had been sitting a few months. I ran clean gas and a bottle of quality Sea foam fuel cleaner / additive. Obviously, that didn't fix it.
Early on, the problem could be described as an occasional sputtering, chugging, but without any popping or back firing. It normally lasted only a few minutes then went back to purring like a kitten with plenty of power on it's own. The check engine light also blinks during the sputtering period.
While I normally get 18 mpg, as the occurrence of the sputtering problem frequency increased, the mileage sometimes drops to 12 mpg...
More recently, the problem occurred like clockwork when I shut it off to fill up and restarted. It lasted only long enough for me to idle through the parking lot and stopped as I got back on the road. Thinking it may have something to do with the old, cruddy, fuel cap, I replaced it with the recommended unit from Auto Zone.
While there I had them read the codes. Nothing jumped out at me, but they mentioned (from memory) a random misfire on cyl #3, some sort of fuel line issue (vacuum issue?), etc.
I then checked all vacuum lines and fixed a couple of minor leaks due to deteriorated lines / fittings.
I should mention that the exhaust was rotted off from the Cat back when I got it and I replaced the rotted items with a turbo muffler, and a tailpipe. The problem was no different before / after.
Most recently, as the malfunction frequency continued to increase, and NOT go away on its own but rather continue as you drive, the following occurred....
I drove it on the highway for approx 40 miles. All ok. Oil pressure always reads max. Water temp was normal at 200*. Upon reaching my destination, I noted a bit more engine / valve-train noise than usual.
After it sat for several hours, I started it and the popping, pulsing through the gas pedal, back firing at an idle started (first time ever).
I checked the oil which was still clean and at the proper level, but I observed (first occurrence) nasty, flakey, carbon flakes on the dipstick above the oil level.
Having no other choice, I drove it home.
The backfiring stopped just above idle. It sputtered during acceleration, however once at speed, it smoothed out, but had a noticeable reduction in power. It ran ok at a steady 60-70 mph, but was weak going up hills.
Since then I checked the oil again – proper level, clean, and with no water. The coolant level was a bit below the proper level but not milky either.
The popping is really bad and I have stopped running it until I can figure out what is happening.
I thank you all in advance for your help.
Merry Christmas!
Rick
https://onedrive.live.com/?cid=9EF666F89D644D14&id=9EF666F89D644D14%213293&v=3
