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The 94-97 7.3L PSD fuel pump is located in the engine valley behind the
fuel filter bowl and is a mechanical pump that has a lifter that is operated by
the camshaft.

It is a triple action pump in that it has a diaphram section and 2 pistons. The diaphragm provides the suction or "lift" to the fuel from the tank and delivers
the fuel to the drivers side piston. This piston pumps the fuel through the

filter at about 10 psi and delivers the fuel to the passenger side piston which

pumps the fuel out to the fuel rails at about 50 psi at idle.
Probably the number one reason to replace this pump is fuel leaks.

It can be difficult to find a leak on the pump but the use a of telescoping mirror

Three places to look are:

1. The main crimp on the pump body which is about 3 inches in diameter.
2. Weep hole number one. While leaning over the radiator, feel under the crimp, in
front of the passenger side piston tower.The hole is about 1/8" in diameter, is
aiming down and should be dry.
3. Weep hole number two.This one aims at the passenger side and is right at the base of the pump where it goes into the block, it should be dry.

It is important to eliminate all fuel leaks as they can cause bubbles in the fuel which will shorten pump and / or injector life.


The 99-03 7.3L PSD fuel pump is located on the drivers side frame rail and is an electric pump. Pressure reading will be needed to diagnose this pump unless it won't run and it has voltage. If the fuel pressure for one bank is lower then the other

replace the check valve for that bank. To eliminate the fuel pressure regulator,

check fuel pressure before and after the FPR.


Fuel Pump General Info