Engine Rough Idle after Timing Chain Replacement - No Codes


New Member
Apr 21, 2003
Calhoun, Georgia
2005 V6

We recently replaced the left cassette and the main chain and tensioners.

The car has a rough idle and shaking. It drives much smoother during acceleration and cruising., albeit not perfect.

About 50 miles have been put on the car since the repair job. Sometimes at speed the MIL will flash, indicating a misfire, but no codes are stored.

My compression guage has went missing, so I removed the cams and all valves were level in the top position. I assumed this would indicate no bent valves. I did not pull off the heads.

Also, the harmonic balancer is either not fully seated, or I damaged it upon removal using the HFT puller as the belt is off about 1/8".

Would the car run at all, or go 50 miles if valves were bent? Could the harmonic balancer not being fully seated cause the rough idle?

I've checked for vacuum leaks, none immediately found.

I will purchase another compression gauge and check that. And I know I have to address the balancer issue anyway.

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