I have been very fortunate so far. Mechanic said I needed full tuneup with all new coils and plugs. Just this spark plug threads problem. We've had it repaired twice already, and it still needs more work. Long story short we created a vapor lock in my exhaust system. Then needed to have the break system controller replaced.
Created wear on pads and extreme heat to rims. My state has a emissions check every few years. Had it checked but needed fully charged battery to do so. Problem switching from cold to hot persisted. Research on the internet suggest this is a reacting problem with this model. They told me it in no way affects my engine and is not letting bad emissions of any consequence into the air.
I took it to my mechanic and they diagnosed it as a small emissions sensor on top of the gas tank. Which did not cure the problem. They tell me this is a known issue with this engine. Fords traditionally have 10 year life on spark plug engine threads. . Interior Door panel was removed and speaker wire connections were checked and problem couldn't be duplicated at dealership, but continues to occur.
All cylinders still full power. All of this was expensive and resulted in having to find transportation for 3 weeks while was repaired. I chose not to have it fixed. . .
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