I have a 2004 f150 5.4l with 93000 miles on it. A few months ago I began having problems which got worse over time. When I start to go up a hill my truck starts to shutter and loose massive power where I can only go about 30 mph. When I put the overdrive OFF. It helps a little. But I usually take my foot off the gas and re apply it and it smooths out. My engine light comes on consistently until it starts to shutter again. Then it blinks and the ac starts kicking out worm air until it smooths out again. The engine runs rough and eats gas like crazy sense this started. I took it into a shop and hooked up a code reader which he said something was wrong in cylinder 7. We believed it was the spark plug so he changed it then switched the coil with number 5 to see if that's the problem. After leaving the shop it continued to do the same thing. I replaced the two coils on number 5 and 7 to see if that would work. It didn't help at all. After he reset the check engine light it came back on the second day. I took it into auto zone yesterday and had them hook up a code reader which showed codes, p0174, p0307, and p0316. It said number 7 cylinder is missfiring but I had the plug changed. I also replaced the fuel filter and no change. Does anyone know what this could be. Maybe a stuck fuel injector? But There is two other codes as well, "fuel trim bank two condition, and crank sensor condition." Would a fuel injector cause the engine to shudder while going up hill?

 

This is the wrong place to post this, you would probably get more help in the engine section of the forum.