Envoy 2WD V8-5.3L (2007)
1. Ignition OFF, relieve the fuel pressure. Refer to Fuel Pressure Relief.
2. Install the J37287 between the fuel feed pipe and the fuel rail.
3. Open the valve on the J37287.
4. Ignition ON, command the fuel pump relay ON with a scan tool and bleed the air from the fuel pressure gage.
5. Close the valve on the J37287.
6. Verify that the fuel pressure does not decrease more than 34 kPa (5 psi) in 1 minute.
‹› If the fuel pressure drops, locate and replace the leaking fuel injector.
7. If the fuel system test normal, replace the fuel pump.
* Relieve the fuel pressure to 69 kPa (10 psi). Verify that the fuel pressure does not decrease more than 14 kPa (2 psi) in 5 minutes.
‹› If the fuel pressure decreases more than the specified value, replace the fuel pump.
* Remove the J37287 and J34730-1A.
* Operate the vehicle within the conditions of the customers concern while monitoring the fuel trim and O2 parameters with a scan tool. The scan
tool parameters should not indicate a lean condition.
‹› If the scan tool parameters indicate a lean condition, test for a restricted fuel feed pipe, restricted fuel filter, or poor connections at the harness
connectors and ground circuits of the fuel pump. If all test normal, replace the fuel pump.
* If the fuel system components test normal, refer to Symptoms - Engine Controls. See: Computers and Control Systems/Testing and
Inspection/Symptom Related Diagnostic Procedures/Symptoms - Engine Controls
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure. See: Computers and Control Systems/Testing and
Inspection/Diagnostic Trouble Code Tests and Associated Procedures/Verification Tests and Procedures
* Fuel Injector Replacement
* Fuel Sender Assembly Replacement
