My truck has 134,000 miles on it and I put champion 1 piece plugs in at around 100,000 miles. My check engine recently came on so i pulled the code P0300-random misfire. I figured maybe it was the coils since ive never replaced them but didn't want to replace all of them. I took it to ford for a diagnostic, they said it needed a fuel injector cleaning and that it needed motorcraft plugs put back in it. I told them not a chance. They also tested the coils and said they were fine. How long are champion plugs supposed to last?

 

I got the same results from my ford dealership. Total cost was around 1200 bucks. Dont blame you for saying no chance. I would have put the OEM plugs as a replacement in the first place though. Try cleaning the boots on the coils. Get a tube of silicone greese and clean them or replace the boots. The boots are only like a dollar a piece at autozone.

 

Yeah, my truck has 170k on it and when I am going highway speeds (70-80) while going up a hill or have a load on the motor prior to it downshifting it would stutter. Felt identical to a misfire and the CEL was flashing (misfire). So I took the coils off and put some dielectric grease in the boot, put back on and no more issues.

Best of luck! If nothing else you have learned a valuable lesson. Never, under any ordinary circumstances visit the stealership for anything minor. Only in a dire emergency or chaotic lapse of self confidence should this act be committed.

 

Whens the last time you replaced the fuel filter? Is you air filter
clean?