Question

Got a P0301 code on my 2002 Chevrolet Impala 3.4L. Runs fine except for the loud valve lifter type sound could it be an injector?

Answer 1

P0301 Misfire number 1 cylinder, Lifer does not make loud noises, You will have to pull the valve cover off. You may be having a rocker arm that has work it way out, There is a TSB dealing with a Rocker arm bolt tightening specification uipdate and make sure the pushrod are not bent. TSB Bulletin No.02-06-01-034

Answer 2

P0301 CHEVROLET Code - Cylinder 1 Misfire Detected
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