Q: Rough idling misfire & a thumping sound from the front of engine

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I replaced the timing gear & chain on Land Rover discovery, oil pump & engine head.the vehicle still have a rough idling ,a flashing check engine light,misfire codes cyl 2&8 misfire,I took a vacuum test says late engine timing.Can this be a faulty cam position sensor?

My car has 128000 miles.
My car has an automatic transmission.

Hello. It sounds like your cam timing may still be off or there may be another issue. I would typically do a compression test first. If the compression is low on only a couple of cylinders, then you have an internal engine problem. If it was low on all cylinders, then you have a timing issue and need to recheck the recent work that was done. If the compression is fine, then you have another issue which may be related to ignition timing or you may simply have a coil or injector issue. These parts would have to be tested separately to isolate the cause of your rough idling issue. A thorough diagnosis of the Check Engine Light code and relevant systems will also help to pinpoint the problem.

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