If this is addressed somewhere that I have missed then I apologize but I have not found anything to help with this truck. A little history. I purchased this barely running and finally discovered the reluctor wheel had been destroyed by the timing chain. So I replaced the guides and tensioners. The next day the truck starting running extremely rough. Found the spark plugs were all in terrible shape. Replaced all of those with the correct motorcraft plugs. Thought problem was fixed. Literally, one day later, the truck came up with P0172 and P0175 and the truck was down on power. So in the 5 months or so that I have owned this lawn ornament, I have driven it a total of less than 50 miles in the last 3 days total. I have thoroughly cleaned out the maf. The throttle body was replaced due to sticking gears less than two weeks ago so tps and tac are also new. There are absolutely no vacuum leaks. I am unsure how to get a fuel pressure reading from this thing being that there is no access port on the fuel rail. All I can do is get vacuum from scanner, which shows 40psi. Unhooking shows no change really. Disconnecting sensor spiked it to 80psi, although I am unsure this really does anything. Test driving it with either of those disconnected changes nothing. One thing of note. It idles at 600-650 for about a minute after you start it hot or cold then slowly seems to make its way to 950-1000rpm and sits there til next shut off. Sorry for the longwinded post. I am simply typing as I think here. If you need any scanner readings I will get them up. Thanks for any input.

 

Have you checked the fuel control module on the frame behind the spare tire? They get corroded and break. Just a thought.