Silverado 1500 2WD V8-6.0L Hybrid (2009)
kPa (43 - 45 psi).
Circuit/System Testing
Important:
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The fuel pump may need to be commanded ON a few times in order to obtain the highest possible fuel pressure.
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DO NOT start the engine.
1. Ignition ON, engine OFF, command the fuel pump ON with a scan tool and observe the fuel pressure gage while the fuel pump is operating. Verify
the fuel pressure is between 345-414 kPa (50-60 psi).
‹› If the fuel pressure is greater than the specified range, replace the fuel pump module.
‹› If the fuel pressure is less than the specified range, test, inspect, and repair the items listed below. If all items test normal, replace the fuel
pump module.
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Restricted fuel feed pipe
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Inspect the harness connectors and the ground circuits of the fuel pump for poor connections.
2. Verify that the fuel pressure does not decrease more than 34 kPa (5 psi) in 1 minute.
‹› If the fuel pressure decreases more than the specified value, perform the following procedure:
1. Ignition OFF, relieve the fuel pressure. Refer to Fuel Pressure Relief (With CH-48027) (See: Fuel Filter/Fuel Pressure Release/Service and
Repair/Fuel Pressure Relief (With CH-48027))Fuel Pressure Relief (Without CH-48027) (See: Fuel Filter/Fuel Pressure Release/Service and
Repair/Fuel Pressure Relief (Without CH-48027)) .
2. Install the J 37287 between the fuel feed pipe and the fuel rail.
3. Open the valve on the J 37287 .
4. Ignition ON, command the fuel pump ON with a scan tool and bleed the air from theCH-48027 .
5. Command the fuel pump ON and then OFF with a scan tool.
6. Close the valve on the J 37287 .
7. Monitor the fuel pressure for 1 minute.
‹› If the fuel pressure decreases more than 34 kPa (5 psi) within the specified time, locate and replace the leaking fuel injector(s).
‹› If the fuel pressure does not decrease more than 34 kPa (5 psi) within the specified time, replace the fuel pump module.
3. 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 module.
4. Operate the vehicle within the conditions of the customer's concern while monitoring the fuel pressure with theCH-48027 . The fuel pressure
should not drop off during acceleration, cruise or hard cornering.
‹› If the fuel pressure drops off, test, inspect, and repair the items listed below. If all items test normal, replace the fuel pump module.
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Restricted fuel feed pipe
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Inspect the harness connectors and the ground circuits of the fuel pump for poor connections
5. If the fuel system tests normal, refer toSymptoms - Engine Controls (See: Computers and Control Systems/Testing and Inspection/Symptom
Related Diagnostic Procedures/Symptoms - Engine Controls) .
Repair Instructions
Perform theDiagnostic Repair Verification (See: Computers and Control Systems/Testing and Inspection/Diagnostic Trouble Code Tests and
Associated Procedures/Verification Tests and Procedures) after completing the diagnostic procedure.
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Fuel Hose/Pipes Replacement - Chassis (2500/3500 Regular Cab) (See: Fuel Delivery and Air Induction/Fuel Supply Line/Service and Repair
)Fuel Hose/Pipes Replacement - Chassis (2500/3500 Crew Cab) (See: Fuel Delivery and Air Induction/Fuel Supply Line/Service and Repair)Fuel
Hose/Pipes Replacement - Chassis (1500 Extended/Crew Cab) (See: Fuel Delivery and Air Induction/Fuel Supply Line/Service and Repair)Fuel
Hose/Pipes Replacement - Chassis (1500 Regular Cab) (See: Fuel Delivery and Air Induction/Fuel Supply Line/Service and Repair)Fuel
Hose/Pipes Replacement - Chassis (1500 Extended Cab - w/8 Ft Bed) (See: Fuel Delivery and Air Induction/Fuel Supply Line/Service and
Repair)Fuel Hose/Pipes Replacement - Chassis (2500/3500 Extended Cab) (See: Fuel Delivery and Air Induction/Fuel Supply Line/Service and
Repair)
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Fuel Injector Replacement (See: Fuel Delivery and Air Induction/Fuel Injector/Service and Repair/Removal and Replacement)
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Fuel Tank Fuel Pump Module Replacement (25 Ext/Crew Cab w/26 Gal Tank) (See: Fuel Delivery and Air Induction/Fuel Pump/Service and
Repair)Fuel Tank Fuel Pump Module Replacement (15/25 Reg/Ext/Crew Cab w/34 Gal Tank) (See: Fuel Delivery and Air Induction/Fuel
