CUSTOMER CONCERN Engine misfires with no compression on cylinder 3, no oil showing on the dipstick, multiple misfire codes, P1268, P128A, and P2646. CAUSE Compression testing confirmed internal engine and valve damage: cylinders 2 and 3 had no compression and cylinder 4 was also low. CORRECTION Remove and replace the damaged engine assembly, correct the oil level, clear DTCs, and verify compression and engine operation.