I have an unusual problem that I can not resolve and would like some advice. I am the proud owner of a 2002 CC with a rough idle once the engine warms up. Cold it idles great. I have tried all the usual solutions, cap, rotor, plug wires, plugs. No vacuum leaks, intake manifold gasket has been replaced. Diagnostics with a good tester reveals an intermittent skip on cylinders one and three. Most of the time it is more "inter" than "mittent". However, on rare occasions it will idle acceptably. SES light is not on, no error codes.
Any Thoughts?
Intermittent Miss, Rough Idle
Moderator: F9K9
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LoneWolf04
- Crew Elite
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- Joined: Sun Dec 19, 2010 9:18 pm
- Location: Grand Blanc, MI
Re: Intermittent Miss, Rough Idle
How many miles do you have on the vehicle? I know the distributor gear wears on these pretty good. I replaced my distributor at 68k miles due to wear. Are you still running the stock fuel injector setup? They were updated as well.
Re: Intermittent Miss, Rough Idle
Mileage is 172K give or take a few hundred. Distributor and fuel injector are original (I am the original owner). Distributor is not difficult to pull and check for excessive wear. Is replacing the injector a mandate, or is there a definitive method to confirm that it needs replacement? They are a little pricy as far as I am concerned!
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ApproachMedium
- Crew Elite
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- Location: Jersey Shore
Re: Intermittent Miss, Rough Idle
Sounds like your truck has the same fate as mine. Mine started out as only throwing the CEL every once a month or so. Now it pretty much will never go away. From the day I bought it, it had a rough idle. Since your mileage isnt as bad as mine yet, its probably a burnt valve or something which is what we believe mine is. Do a compression check on those two cylinders and then compare to the rest of the cylinders on the truck.
I have given up on mine at this point, its getting a 5.7L before August.
I have given up on mine at this point, its getting a 5.7L before August.
Knowledge has no value unless its shared with others.
Exploration Machine- 02' CC V8 swap. 300K+
Portable Roller Coaster- 07' MKV VW GTI
Its another Jeep- 98 TJ
Exploration Machine- 02' CC V8 swap. 300K+
Portable Roller Coaster- 07' MKV VW GTI
Its another Jeep- 98 TJ
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LMs10CrewCab
- Crew
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- Joined: Sun Feb 17, 2013 7:15 pm
- Location: Two Rivers Wisconsin
Re: Intermittent Miss, Rough Idle
Hey
Probably not it but I will throw it out:
A dirty MAF sensor ( should be cleaned when air filter is dirty ) and oxygen sensors ( should be replaced every 80k ) could cause rough idle and misses.
I have heard that a dirty MAF filter can cause misses because the air/gas mixture cannot be determined by the sensor.
Oxygen sensors also can cause the same symptoms.
Yours does have high miles - maybe they have not been replaced/cleaned (?)
Have a good day
Probably not it but I will throw it out:
A dirty MAF sensor ( should be cleaned when air filter is dirty ) and oxygen sensors ( should be replaced every 80k ) could cause rough idle and misses.
I have heard that a dirty MAF filter can cause misses because the air/gas mixture cannot be determined by the sensor.
Oxygen sensors also can cause the same symptoms.
Yours does have high miles - maybe they have not been replaced/cleaned (?)
Have a good day