The spark plugs may become dislodged from the cylinder heads. A loud popping noise can be heard and a subsequent misfire experienced. The threads on the spark plug ports in the cylinder head(s) can become stripped or missing when the spark plug is dislodged. The threads in cylinder heads may be replaced using “Lock-N-Stitch” aluminum inserts. Our technicians tell us thread replacement is performed when the vehicle is out of base warranty. Vehicles under base warranty receive a new cylinder head.
Average mileage: 140,000 (105,000–175,000)
Engines affected: 4.6L V8, 5.4L V8
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Blew out #3 spark plug. Also broke the spark plug wire coil bracket when it got kicked out. Looking for solution now.
When I crank it loud pop noise an the knocking noise an spark plug gets dislodged
Blew the plug on number 4. Threads were gone, so i installed the thread inserts. Now dealing with misfire on the same cylinder (code P0304)- No resolution yet.I'm going to start with the plug wires and coil pack.