Close
GMC 1500 Pickup Problems

Engine Misfire Due to Worn Valve Seat on GMC 1500 Pickup

Problem Description and Possible Solution

The engine may develop a misfire due to worn valve seats. This fault will cause the Check Engine Light to illuminate. Our technicians tell us the misfire may or may not be felt while driving. They further recommend that both cylinder heads be removed and thoroughly inspected and repaired as necessary.

(5 people reported this problem)

GMC 1500 Pickup Vehicles With This Problem

RepairPal Verified
Average mileage: 135,000 (135,000–135,000)
Engine affected: 5.7L V8
4 model years affected: 1996, 1997, 1998, 1999
Not Your GMC 1500 Pickup Problem?
Brake problem? Or maybe a faulty head gasket cylinder?
Learn About Your Car Problems
Search For a Specific Car Problem
Viewing 1-1 of 1 comments
check engine light won't go out. Po300 and PO306. Engine runs smooth. Did full tune up-cap, rotor, plugs, wires, even replaced 02 sensor and all fuel injectors. Code still on but truck runs fine