Repair 7

How to Change a Fuel Control Regulator on a 2002 Chevy Trailblazer

General Motors (GM) introduced the Chevrolet Trailblazer as an upscale version of the Blazer in 1999. The 2002 Trailblazer has a six-cylinder 4.2-liter engine with sequential fuel injection. This engine requires a fuel pressure regulator -- also known as the fuel control regulator -- to maintain the pressure in the fuel system at the correct level. The replacement procedure for the fuel control regulator is the same for all Trailblazers.

Instructions

1

Remove the cable from the negative battery terminal. Open the filler cap on the fuel tank to release the pressure in the fuel tank.

2

Connect a fuel pressure gauge to the pressure fitting on the inlet fuel line. Place the bleed hose of the fuel gauge into a container approved for gasoline. Open the valve on the pressure gauge to relieve the pressure in the fuel system. Drain the fuel from the pressure gauge into the container, then disconnect the pressure gauge from the pressure fitting.

3

Disconnect the outlet resonator for the air cleaner with a socket wrench. Release the retaining clips for the main wiring harness on the front of the engine, then detach the wiring harness.

4

Remove the vacuum line from the fuel control regulator. Clean the surrounding area with a shop rag. Release the retainer on the fuel return line for the fuel control regulator, then detach the fuel return line. Release the retainer for the fuel control regulator with a socket wrench. Detach the regulator from the fuel rail. Discard the O-ring on the fuel control regulator.

5

Install a new O-ring to the new fuel control regulator, and coat the O-ring with engine oil. Push the new fuel pressure regulator into its housing on the fuel rail. Attach the retainer for the fuel control regulator, and tighten it to 71 inch-pounds with a torque wrench.

6

Attach the retainer for the fuel return line to the fuel control regulator. Tighten its retainer screw to 71 inch-pounds with a socket wrench. Connect the fuel return line for the fuel control regulator.

7

Fasten the filler cap on the fuel tank, and connect the cable for the negative battery terminal with a socket wrench. Turn the ignition on for two seconds to prime the fuel system, then turn it off for 10 seconds. Turn the ignition back on and check for fuel leaks. Connect the engine wiring on the front of the engine, and attach its retaining clips. Install the resonator for the air intake.