5.4 p0307 misfire
#1
07-07-2009, 07:00 PM
5.4 p0307 misfire
Truck: 02 f250 4x4 5.4 manual trans w/ 120k. Problem started with an occasional misfire. Every time a misfire has registered its been cyl 7. I replaced plugs and all was good for approx 1k, then a regular misfire occurred. I pulled the plug and it was heavily fouled. I moved the cyl 1 plug to cyl 7 and still misfire on cyl 7. Then I moved cyl 1 COP to cyl 7 and still misfire on cyl 7. Next I pulled the fuel rail and swapped injector 7 with injector 5. All was good for approx 1k. P0307 has returned. I've shaken the wires and checked the obvious connections, but can't figure out the problem. As I drive, cyl 7 is normally dead but occasionally you can feel the motor buck as it fires. Any ideas for anything else I should check under my shade tree? thanks, Bart
#3
07-12-2009, 08:36 PM
think i have the same problem
I have a 1998 f150. It all started 3 or 4 moths ago, the truck has bout 160k so when it started missin i just replaced all the coil packs and spark plugs, I went to NAPA and priced the packs and they were 60 bucks a piece. So I got on ebay and bought a set of 8 for 100 bucks and put them in. Truck ran awesome for about 3 months and started missin again, crap! So I plugged it in and of course it was missin on #4 replaced that with one of the old ones that was still good. ran good for a couple weeks the started missin intermititly, then i drove it last night and wow it ran like crap. got home from my very aggrivating trip and plugged it in and i had a random/multiple misfire and a #7 misfire code. Not really sure what to do. from what it sounds like my best bet would be to take it to a shop and have them look at it. or take out all my cheapo coil packs and replace them with better ones. getting very frustrated, just wondering if anyone had any advice, Thanks
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