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I was involved in a light accident over the weekend. I was hit in the rear by a Prius which didn't do body damage except for the 7 blade harness for my trailer towing. But, now the truck has a random misfire code. You can feel the truck jerk when you go up any grade. We changed the fuel filter and dumped in some cleaner already. One guy says its fuel and one thinks its coils. It is a 2003 F150 extended cab 5.4 with a nearly new motor. The truck has about 175xxx on it and I have had it for about 40xxx. I have not changed coils. We did check the inertia switch on the passenger side and it was not tripped. If anyone has an idea I'd love to hear it! Thanks in advance!
A case like this could be just a coincidence so you have to go in search and not just change parts on a hope.
To see if it is a coil, use a Scanner to look at mode 6, test 53.
This is Ford speak. Any specific Scanner may display it different.
There you will find a record of each cylinder's misfires if there are any.
If one is 'out of limits' that is your culprit.
It will not set a code because that memory location has no ability to set any code.
Good luck.
Good news! Evidently on the way home today it pitched a code. Number 4 tripped and it was the same one that tripped once about 2 years age. The boot was cracked. I also had a hole on the under side of a bend in a vacuum line. We've all heard the saying "When it rains it pours"! Thanks!