I just replaced the injector pump and lift pump on my 01 dodge. The truck will not go no matter how hard you mash the pedal until it warms up some. Could it be the throttle positioning sensor.
Thanks!

 

check your codes

 

Yes, it can be. Do the TPPS reset, then clean your IAT and MAP sensors. Those sensors are also easy to test, so test to make sure both are up to snuff.

If that does not correct the problem then check your fuel pressure between the lift pump and the VP44.

If the fuel pressure is below 9 psi, either the computer in the pump or the back housing of the VP44 is blown out (real common on inexpensive rebuilds from other than reputable performance shops), or the new lift pump has a stuck bypass valve (also all too common on new OEM transfer pumps).