onlyexilove
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So I have the wonderful P0304 code that a lot of the Gen 2 Expy's get. My wife's 2004 5.4L 2V popped this code a few months back and it comes and goes. Initially swapped all coil packs and spark plugs (needed them based on age) and the code came back. I decided to take it up to Ford and see what they thought. They ran a compression test which came back perfect, updated the computer and kept it for about 3 days before calling me back and telling me they couldn't figure it out but it could possibly be the computer. I went ahead and swapped the computer after talking to a friend of mine and also went ahead and swapped all 4 of the O2 sensors. I have visually inspected all of the wiring around the injectors and COPS and didn't see anything wrong. I have pulled the wire harness to each of the passenger side injectors to see if it would have an effect and each made the truck run worse. It has a bit of an idle issue when you first start it up and seems to smooth out after driving it a bit, but still has an odd idle even after running. At this point between Ford and the parts I have installed, I am into this for about $800 and still have the code. One other issue that popped up recently was the fuel pump relay went bad causing the truck to shut down. I ordered the relay and soldered a new one back on the fuse block board and she fired right up and drove at higher speeds with no problem. The truck doesn't seem to lack power and drives pretty good around town and on the interstate. I am basically at a loss and not sure what else to do. Any help and feedback is very much appreciated. Thanks!
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