Last week I had the engine light come on. It was a random misfire P0300 and P0301. I made an appointment to the dealer and have it services. They replaced the NGK platinum with the copper plugs. He also ran some combustion cleaner through the system to get rid of carbon buildup. I picked up the Jeep and drove it for a day. Then the check engine light came on again. Back to the dealer. They performed a TSB 07-007-06 but it did not solve the problem. I'm not sure what this TSB is. They recommended another CCC test because the issue still remained and diagnosis for the intake valve locks (09-007-06). At this time they said its safe to drive. I would have to make an appointment for those tests. I drove it home without any issues. The check engine light must of been reset also.

I drove it to work for two days. When starting the engine one day all of a sudden it began to knock and chatter. The engine was really vibrating. I could even feel feedback through the gas pedal of the knock. Something was rattling in there bad. I called in a tow truck to take it to the dealer. They call me at home and say the bottom end has gone and the entire engine needs to be replaced. They still don't know what exactly broke. The Jeep has 90,000 miles on it. Its in mint condition. What the hell could of happened? Could this of been the result of the valve locks? I need your feedback on this.

Same issues as mine (2006 3.7L with 47k miles)
started as random misfire codes, then showed up as cylinder 3, started running worse everyday and it hated to start when the engine is warm.
Took it to a repair shop. They first said it was the valves going out, I ordered a teardown and now they think it might only be a blown head gasket.
Still waiting on the final information and waiting on the extended warranty adjuster to show up and decide of they are covering it or not..

Talk to jhblackwell. He has gone through a coding horror-story on his 2006. Sounds very similar. I don't remember what his final solution was but he is not happy with the dealer.

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Colin
LOST#85291
"Blue Bunny"
04 KJ Sport 3.7L AT 4x4
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