Ok here is the deal. I have 2007 F150 with 43,000 miles. It has been babied its whole life besides my heavy foot. WOT on average once a day. About 2 months ago i noticed a weird bogging/ backfiring when accelerating while cold. It has become worse and now it throws a P0308 code (cylinder 8 misfire). It usually only does it when its cold but it has also done it when warm. It gets worse the harder I accelerate. Where do I start in fixing this? No engine mods besides edge evolution. Thanks!

 

Well IDE go for pot number 8.

Swap the COP over to another pot.

If its the same then change the plug. (Nasty)

 

#8=Muphy's Law.

 

UPDATE: I replaced the coil on cylinder #8 and it still misses. Now change the plug? Thanks

 

Thats what id do.

 

my cyl 8 was misfiring changed the ignition coil still did it. Just changed the plug no more misfire. Came out really easy with the truck warm.

 

How many miles do you have on your truck?