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Q: Misfire in cylinder 6. GMC Sierra 1500.

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Replace coil pack,fuel injector, spark plugs, wires. Engine light is on and have rough idle.

My car has 99000 miles.
My car has an automatic transmission.

A: Hey there. You need to have the engine comp...

Hey there. You need to have the engine compression tested to see if you have a leaking valve or rings. You could try to have the combustion chamber cleaned of carbon and see if the problem improves. This may be due to a sticking valve or excessive carbon build up on the intake valve. If compression is low and no leaks are found, then you may have a worn cam lobe. If you would like to have this taken care of, a certified pro from YourMechanic can come to your car’s location to inspect the misfiring problem and have this addressed appropriately.

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