What is causing the driver side rear spark plug to completely burn up and blow out of the hole
A Triton engine I bet. Ford had a lot of trouble with that, they only used 4 threads on the plug, and on an aluminum head to boot. I don't know what they were thinking
You need to put a thread kit in the head on the affected cylinder. FORD had issues with the design of this cylinder head and the sparkplug threads.
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