Fuel Pressure Relief

Engine Controls and Fuel - 5.3L L84 or 6.2L L87 | Repair Instructions | Document ID: 5045797

Warning

Refer to Diesel/Gasoline Vapors Warning.

Warning

Refer to Safety Glasses Warning.

Warning

Fuel that flows out at high pressure can cause serious injury to the skin and eyes. ALWAYS depressurize the fuel system before removing components that are under high fuel pressure.

Warning

Relieve the fuel system pressure before servicing fuel system components in order to reduce the risk of fire and personal injury. After relieving the system pressure, a small amount of fuel may be released when servicing the fuel lines or connections. In order to reduce the chance of personal injury, cover the regulator and the fuel line fittings with a shop towel before disconnecting. This will catch any fuel that may leak out. Place the towel in an approved container when the disconnection is complete. Fuel Tank Storage Insert a capless adapter funnel or equivalent into the capless fuel fill pipe and relieve the fuel system. Fuel System Scan Tool Method — Preferred

1. Install a scan tool and turn the ignition ON.
2. Using the scan tool, command the fuel pump OFF allowing the low pressure fuel pump to shut off.
3. Start the vehicle and allow the engine to idle until the engine stops. The engine will stop in approximately 5-20 seconds.
4. Repeat step 3. Using the scan tool, verify pressure has dropped to a minimal level.
5. Turn the ignition OFF.

Note

To avoid fuel spillage.

6. Disconnect the battery negative cable. Battery Negative Cable Disconnection and Connection
7. When the fuel system repair is complete, connect the battery negative cable. Battery Negative Cable Disconnection and Connection Alternate Method — If a scan tool is not available
8. Disable the fuel pump by removing the B+ fuel pump control module fuse. Electrical Center Identification Views
9. Start the vehicle and allow the engine to idle until the engine stops. The engine will stop in approximately 5-20 seconds.
10. Attempt to restart the vehicle to ensure pressure has dropped to a minimal level.
11. Turn the ignition OFF.

Note

To avoid fuel spillage.

5. Disconnect the battery negative cable. Battery Negative Cable Disconnection and Connection
6. When the fuel system repair is complete, connect the battery negative cable. Battery Negative Cable Disconnection and Connection