I have a 2004 F-150 4wd. 5.4 3 valve. Started out with a P0171 (left bank lean) after changing a vacuum line both left side O2 sensors and MAF sensor code went away. Now showing the P0193 code. My question is whether or not the fuel sensor is the problem or possibly the TPS. Truck chugs with rapid throttle inputs but if you hold it steady it will eventually smooth out. The Ford service department here says i can change the the TPS but my Haynes manual says i can't. Who is right?

 

I don't have any direct experience with that engine but I can't think of any reason why the TPS couldn't be replaced. My hunch is that if the dealer says it can, it can. Your symptoms do sound like a TPS malfunction plus, if the fuel sensor were bad, it seems that the engine would continue to run rough not smooth out.

 

The TPS is replaceable. The manual states to use a heat gun to heat the screws that hold it on to make it easier to remove. Just be careful where the heat goes to. It can distort plastic parts and cause more problems.