I drive a 2005 Ford F250 Lariat with the V10 Triton. It's got 153,000 miles on it and runs like a scalded puppy...except when the fuel level gets below 3/4(when it's hot) and 1/2(in colder weather). When I get to 3/4 tank, it is hard to start and idles roughly for about 30-45 seconds. It will generally even out the idle after it warms up, and runs mostly ok...if I don't top off with gas, I get a P0306 code after 3 or 4 more starts. I've replaced the plugs and coils about 40,000 miles ago, and I cleaned the TB and MAF sensor recently with no difference. Also, the EVAP drive cycle will not complete after I disconnected the battery. I'm stumped...
Well since it has to do with the level of the gas replace the fuel pump and the fuel filter if it doesn't pump enough fuel it can make the engine misfire
I was hoping you weren't going to say that. I forgot to mention the fuel filter was replaced about a month ago. I have a buddy with a fancy Snap-on scan tool, so I'll ask him to check the fuel pressure before I drop the money on a new pump. Good thing I work at a parts store and get a hefty discount on parts. Thanks, Scotty!! And Go Illini!(grew up in Peoria)