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Step 6 - Once the fuel gauge had been attached, turn the ignition key to the "ON" position. The gauge should jump up to 45 - 60 pounds (most vehicles.)

Fuel Pressure

Step 7 - While the engine is running, the fuel pressure should drop about 5 psi, then snap the throttle, the fuel system pressure should jump up about 5 psi., this means the fuel pressure regulator is working properly. If the system fuel pressure does not respond inspect the vacuum feed line, if okay, the fuel pressure regulator has failed.

Operating Fuel Pressure

Step 8 - After the test is complete install a shop towel at the base of the test port which will be used to gather excess fuel from the gauge hose.

Install Shop Towel

Step 9 - While using the shop towel to gather excess fuel, loosen the pressure hose, fuel will begin to leak out.

Gauge Pressure Hose

Step 10 - Once the hose has been removed, fuel will continue to leak out, move the hose end onto a shop towel to collect excess fuel.

Fuel Leakage