Ok im lost got a 02 that has no codes has a new vp and lift pump new fuel filter the truck chugs and dies when it gets to 2000 rpm checked fuel pressure and everything is great im lost

 

The symptoms you describe sound as if the front bypass diaphragm on the rebuilt VP44 is blown and causing the timing valve that regulates the fuel delivery to oscillate and drop pressure to the injectors and shut down the engine. That will not throw a code.

However, check all your fuel hoses and filters for air leaks before assuming it is the pump. Rule of thumb, if the hoses (all of them, including those on the top of the tank) are more than a couple years old replace them. They develop microscopic holes that allow air infiltration. Then double check your fuel filter and the seals on both the filter housing and the fuel heater located in the same assembly.

All that being good, then verify that the connector to the computer on the VP44 is both clean and dry, and no corrosion. Then lube it with dielectric grease and reinstall it.

If you are working on a truck in weather below 10 degrees F, also figure your fuel has ice and paraffin crystals that will suck up and block the screen in the fuel tank. Warming the fuel will solve this, then add a fuel additive to eliminate the problem. If this is the problem, let the truck run at a fast idle for about 20 minutes, after it is fully warmed. Then the fuel will warm enough for the problem to go away.

 

this was a overnight thing onlything that changed was fuel additive i havent checked the fuel filter in the tank but i did blow out the line to the tank to see if it was blocked