Attention: TDR Forum Junkies 
A good friend of mine has a 99 3500, CTD and 5spd. When he bought it I advised him to get a fuel pressure gauge. After one day when it quit running he bought a VP44 and lift pump, he then put on an Edge Attitude with Juice so he could monitor everything. Since he put on the new VP and LP it has been steady 14 psi at idle, and he could pull it down to 5-6 psi on level 5 running the crap out of the truck. In normal driving on level 3 fuel pressure always stayed above 8. On a recent trip the fuel pressure monitor warned him of low fuel pressure. He had to set the Edge to the lowest setting and baby it to keep it above 5 psi towing his trailer. We put on another lift pump. Could get 12 psi, but just revving the engine with no load would pull the pressure down to 8 psi. He has sence put on an Aeromotive fuel pump, bypassed the factory lift pump, and factory fuel line. He has changed the fuel filter 3 times. He has inspected and changed the check valve on the return line, changed the fuel pressure sensor, and even dropped the tank looking for plugged supply line.
Now for my questions.
What regulates fuel pressure in the VP44? The check valve or is there something else?
What else do we need to check to get that fuel pressure back?
The VP and first LP have maybe 10,000 miles on it them now. It tows and spends most of its time on level three.
Thanks for the help and your time.
Michael
Now for my questions.
What regulates fuel pressure in the VP44? The check valve or is there something else?
What else do we need to check to get that fuel pressure back?
The VP and first LP have maybe 10,000 miles on it them now. It tows and spends most of its time on level three.
Thanks for the help and your time.
Michael
