Service Procedure
Important:The service procedure contained in this recall is different from the service procedure found in the appropriate service manual. As a result, the labor time allowance has been revised to correspond with this new service procedure.
Service Procedure - Light Duty Trucks (Silverado, Suburban, Avalanche, Sierra, Yukon XL)
1. Unsnap the intake manifold sight shield from the stud.
2. Remove the sight shield from the sight shield bracket.
Caution:
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.
J 34730-1A Fuel Pressure Gage
3. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in SI.
4. Loosen the fuel fill cap in order to relieve fuel tank vapor pressure.
5. Remove the fuel rail pressure cap.
6. Connect the J 34730-1A to the fuel pressure valve. Wrap a shop towel around the fitting while connecting the gage in order to avoid spillage.
7. Install the bleed hose on J 34730-1A into an approved container.
8. Open the valve on the J 34730-1A in order to bleed the system pressure. To assist in relieving residual pressure in the fuel rail, push down on the fuel rail dampener. The dampener should move inward approximately 2-3 mm (1/8 in) as the pressure releases from the system.
9. Once the system pressure is completely relieved, remove the J 34730-1A.
10. Remove the bleed hose on the J 34730-1A from the approved container.
11. Remove the shop towel from around the fitting and discard into an approved container.
12. Disconnect the J 34730-1A from the fuel pressure valve.
13. Drain any fuel remaining in the gage into an approved container.
14. Install the fuel rail pressure fitting cap.
15. Clean any dirt from the fuel pressure dampener (i.e. damper) retainer (clip) and the surrounding area.
Caution:
If the fuel pressure is not relieved as instructed in Step 8, or the dampener is not held in position during the replacement of the dampener clip, the dampener 0-ring may not seat or seal properly. A damaged or improperly seated 0-ring may result in a fuel leak. A fuel leak in the presence of an ignition source may result in a fire.
Caution:
Do not remove the fuel dampener from the fuel rail. If the dampener is removed, a fuel dampener kit with a new 0-ring must be installed. If the dampener and 0-ring is not replaced, a fuel leak may result. Clean dirt and/or debris from dampener cavity and lubricate the new O-ring with clean engine oil prior to installation of the dampener.
Notice:
Push down on the fuel dampener until Step 16 and 17 are completed to avoid damaging the dampener 0-ring.
16. Push down on the fuel dampener and remove the fuel pressure dampener clip (1). Discard old dampener clip.
17. Push down on the fuel dampener and install the fuel pressure dampener clip (1).
18. Install the fuel fill cap.
19. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in SI.
20. Use the following procedure to inspect for leaks:
20.1 Turn the ignition ON, with the engine OFF, for 2 seconds.
20.2 Turn the ignition OFF for 10 seconds.
20.3 Turn the ignition ON, with the engine OFF.
20.4 Inspect the fuel rail, fuel rail dampener, and fuel rail pressure cap and valve for leaks.
If a leak is present, a dampener kit with new 0-ring must be installed. Relieve the system pressure as described in Step 4-14 above. Clean dirt and/or debris from dampener cavity and lubricate the new 0-ring with clean engine oil prior to installation of the dampener. When finished, repeat Steps 20.1 - 20.4.
21. Install the intake manifold sight shield to the bracket.
22. Snap the intake manifold sight shield onto the stud.
23. Close the hood.
Service Procedure - Medium Duty Trucks (Chevrolet Kodiak and GMC TopKick)
1. Turn the wheels to the left.
2. Tilt the hood open.
3. Remove the clip retaining the wheel housing panel to the radiator support bracket.
4. Remove the clip retaining the wheel housing panel to the rear cowl panel.
5. Remove the wheel housing panel, from the retainer tabs.
6. Remove the wheel house panel from the vehicle.
7. Remove the Under Hood Fuse Block Cover.
8. Remove the 20A/25A ECM-B/FUEL PUMP fuse.
9. Start the engine to relieve fuel rail pressure. (Engine should start and stall) To assist in relieving residual pressure in the fuel rail, push down on the fuel rail dampener. The dampener should move inward approximately 2-3 mm (1/8 in) as the pressure releases from the system.
10. Clean any dirt from the fuel pressure dampener (i.e. damper) retainer (clip) and the surrounding area.
Caution:
If the fuel pressure is not relieved as instructed in Steps 7-9, or the dampener is not held in position during the replacement of the dampener clip, the dampener 0-ring may not seat or seal properly. A damaged or improperly seated 0-ring may result in a fuel leak. A fuel leak in the presence of an ignition source may result in a fire.
Caution:
Do not remove the fuel dampener from the fuel rail. If the dampener is removed, a fuel dampener kit with a new 0-ring must be installed. If the dampener and 0-ring is not replaced, a fuel leak may result. Clean dirt and/or debris from dampener cavity and lubricate the new O-ring with clean engine oil prior to installation of the dampener.
Notice:
Push down on the fuel dampener until Step 11 and 12 are completed to avoid damaging the dampener O-ring.
11. Push down on the fuel dampener and remove the fuel pressure dampener retainer (1). Discard old dampener retainer.
12. Push down on the fuel dampener and install a new fuel pressure dampener retainer (1).
13. Install the 20A/25A ECM-B/FUEL PUMP fuse.
13.1 Turn ON the ignition for 2 seconds.
13.2 Turn OFF the ignition for 10 seconds.
13.3 Turn ON the ignition.
13.4 Inspect the fuel rail dampener for leaks. If a leak is present, a dampener kit with new 0-ring must be installed. Relieve the system pressure as described in Step 7-9 above. Clean dirt and/or debris from dampener cavity and lubricate the new 0-ring with clean engine oil prior to installation of the dampener. When finished, repeat Steps 13-13.4.
14. Install the Under Hood Fuse Block Cover.
15. Install the wheel housing panel to the retainer tabs.
16. Install the clip retaining the front of the panel to the radiator support bracket.
17. Install the clip retaining the wheel housing panel to the rear cowl panel.
18. Tilt the hood closed.