Hello i have a 2018 ford f150 with the 5.0 V8 engine. purchased it in July of last year, just a couple weeks after i purchased it it gave me the P0301 code which means misfire on cylinder 1 and so i sent it to a mechanic and they recommended changing all spark plugs and so i replaced all of them (Motorcraft brand).. that seemed to clear my code and the truck ran fine until now, 8 months later the same P0301 code popped up. how can that be if my spark plugs are 8 months old with less than 10k miles on them?.. i also have noticed my MPG gone down from 16 to 14mpg city. anybody had this issue? any help is greatly appreciated, thanks.
Well, it certainly tells you that the plugs weren’t the issue.
I could however, be the coil, etc. Some additional diagnostic work will need to be done and a review of some of your data, etc. You don’t mention if your mechanic moved the coil to another cylinder. If that coil followed another cylinder and the code changed that would indicate the possibility of a bad coil. This doesn’t sound like major problem in terms of being solved. Good luck.....
Always check the 'Frequenly Asked Questions' (FAQ) topic at the top of the page first. There's a whole article dedicated to your trouble code. If you still have questions, let us know.
