I have a 97 F150 5.4l. I have had repeated failures of the left rear COP (when looking at the engine from the front). Error codes have verified diagnosis. I have been told its from the horrible engine design and moisture gets trapped in the spark plug well. I have also been told its due to sediments in the fuel line. I am starting to think its from a nice family of gremlins that have made my engine conpartment a home.

Here's my questions:

1) Do I quit my winning and continiously change the COP?
2) Do I change the fuel filter only?
3) Do I change the spark plugs too?
or 4) Do I clean/replace every part that has to do with the fuel and sparking system (i.e. Clean fuel tank, new fuel filter, COPs and spark plugs, ect.)?

This is a long question, hopefully to be answered with an easy solution.

Thanks for any help

V/r

Mike

 

I am lurking around on the Lincoln LS forum and out of necessity these guys become experts in CoP matters.
Read this:
The Only Coil Thread Needed. Design, Common Issues, Replacement, & MORE Included.