NHTSA Complaint #11668041 — 2021 GMC YUKON XL

Check engine light on, Abnormal engine noise and very significant loss of power. Info registered in the repair invoice: tech verify customer concern, check for code found code p0300 and looking to the live data found miss fire on cylinder number 6, tech swap the coil and spark plug with wire, miss fire still on the same cylinder, tech inspect the injector no problem found, remove the valve cover for inspection found, that the rocker arms is loose, customer approve tear down, tech remove the head on the right side to inspect the lifter and the camshaft, tech found damage on the camshaft, camshaft replacement and lifter is necessary, customer decline repair, tech assemble the engine back and returned to the customer. Customer decide to replace the engine, tech replace the engine test to verify repair vehicle working as design