How to Replace 5.3L Fuel Pressure Regulator

by Blaze Johnson

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The 5.3-liter Vortec V8 engine features an electronic throttle control system, E85 “Flex Fuel” capability, iridium sparkplugs, sequential fuel injection and variable valve timing technology. Designed by General Motors, applications for the 5.3-liter Vortec V8 include the Chevrolet Tahoe, GMC Sierra, GMC Yukon, Chevrolet Silverado, Chevrolet Express and several other vehicles made by the American auto manufacturer. Hard starting, rough idle and poor engine performance could be the result of a bad fuel pressure regulator. Replacing the defective fuel pressure regulator for your 5.3-liter Vortec engine is a straightforward task, when using the proper tools and information.

Step 1

Loosen the vehicles fuel filler cap to help depressurize the fuel system.

Step 2

Remove the fuel pump relay from the fuse panel, located underneath the hood. Consult the owner's manual for the vehicle if you have trouble locating the proper relay.

Step 3

Start the vehicle's engine to fully depressurize the fuel system. When the fuel system has been fully depressurized, the engine will die due to the lack of fuel in the system.

Step 4

Switch off the vehicle's ignition and disconnect the negative battery terminal, using an adjustable wrench.

Step 5

Disconnect the vacuum line attached to the side of the fuel pressure regulator. The fuel pressure regulator resides on the upper driver’s side portion of the engine, directly below the plastic intake manifold shroud (See Resources for example).

Step 6

Remove the retaining clip securing the fuel pressure regulator to the fuel rail. Use a pair of screwdrivers to aid in the removal of the retaining clip.

Step 7

Pull the fuel pressure regulator out of the fuel rail assembly. Remove the O-rings and filter screen from the fuel rail assembly. Discard the old fuel pressure regulator, O-rings and filter screen.

Step 8

Lightly coat the new fuel pressure regulator and O-rings with fresh engine oil.

Step 9

Install the new fuel pressure regulator, with the O-rings and filter screen properly in place. Replace the retaining clip to secure the fuel pressure regulator to the fuel rail assembly. Make sure the retaining clip snaps over the outer ring of the fuel pressure regulator.

Step 10

Reconnect the negative battery cable, replace the fuel pump relay and tighten the fuel filler cap. Prime the fuel system by switching the vehicle's ignition to the “On” position for 3 to 5 seconds. Check the fuel pressure regulator for any leaks.