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F-150 engine coil failure

I have replaced all of the engine coils in my 2001 F-150 (King Ranch edition) twice maybe even three times. Why does this keep happening? Please only post solutions this has become very expensive for me.

Have you replaced your spark plugs in the last 100K miles? Excessive plug gaps can damage your coils.

I have an '04 T’bird with similar COP (coil on plug) issues. I have resolved to replace the “boots” on my coils every 30K miles. I believe the boots deteriorate with heat and time and then allow the electricity to arc between the spring that stretches from the coil down to the plug. Once the arcing starts it eventually destroys the coil.

So, before I fry up multiple and expensive coils I’m going to replace the boots as a preventive maintanence item. NAPA and other parts stores are starting to stock the boots for my T’bird and they cost about $12.00 for a set.

If my theory is correct it will work. If not, I’ll just have to replace all the coils when one starts to crap out. I have replaced about 12 coils on the T’bird in 60K miles of driving, but Ford took care of it under an extended warranty (10 years and 100K miles) on my car.

The coils are about $80 a pop from a Ford dealer. Cheap ones of questionable quality are available on ebay for about $25 ea. Auto parts stores are somewhere inbetween. This is a nuiscense to replace one and a few thousand miles another, then a few more miles another, etc. Otherwise the T’bird runs great, so when they go I’m replacing all of them at one time.

Do you ever wash your engine with a pressure washer or even a garden hose?? This is the kiss of death for Ford coils…If ANY moisture gets down in a plug well, you can pretty much count on replacing that coil… You seldom need to replace them all, the OBD system will pinpoint the failed one(s)…

I definately don’t wash my engines. In my T’bird it has to be missing badly to get a check engine light to come on. Then there are codes stored for sure. Other times when I feel the missing but the CEL hasn’t come on there maybe a code, and there may not be a code. My experience is when one coil fails, another is soon to follow.

That matches my experience, as well as that of several other Lincoln LS owners (same engine).

BTW, I know of one Ford dealer that sells the coils for about $50 over the internet and ships anywhere in the US.