Sierra 3500 4WD V8-6.6L DSL Turbo (2007)
5. Connect the J-45873-30 with yellow hoses to each fuel injector return port of the right cylinder bank, and install the retaining clips.
6. Install the 4 yellow hoses in the J 45873 graduated cylinders in numerical order.
7. Connect the fuel return hoses to the J-45873-30 to prevent leakage.
‹› If the engine starts and runs, idle the engine until fuel start dripping into all the graduated cylinders and yellow hoses are full of fuel.
Important: The engine cranking speed must be more than 150 RPM during the cranking portion of this test.
‹› If the engine does not start, crank the engine in 15-second intervals, with 1 minute cooling time between intervals, until fuel starts to flow into
all of the graduated cylinders.
8. Elevate the 4 yellow hoses to retain the fuel in the hoses, and empty the 4 graduated cylinders into a suitable container.
9. Install the 4 yellow hoses in the J 45873 graduated cylinders in numerical order.
‹› If the engine starts and runs, idle the engine for 15 seconds.
‹› If the engine does not start, crank the engine for 15 seconds.
Important: During replacement of the injectors, inspect the inlet and outlet fittings for corrosion or contamination. Refer to
Contaminants-in-Fuel Diagnosis. See: Computers and Control Systems/Testing and Inspection/Component Tests and General
Diagnostics/Contaminants-in-Fuel Diagnosis
10. Measure the quantity of fuel in each of the graduated cylinders.
‹› If high return flows were recorded, replace those fuel injectors that had high return flow and retest the fuel return flow, referring to Fuel
System Specifications. Replace any additional high return flow injectors and proceed to the next number step.
11. Install and connect all fuel system components that were previously removed or disconnected.
12. Remove the fuel return pipes from the fuel injectors of the left cylinder bank and repeat the fuel return flow test previously preformed on the right
cylinder bank.
‹› If high return flows were recorded, replace those fuel injectors that had high return flow and retest the fuel return flow, referring to Fuel
System Specifications. Replace any additional high return flow injectors and proceed to the next number step.
13. Install and connect all fuel system components that were previously removed or disconnected.
14. Start and idle the engine. You may have to prime the fuel system before the engine will start. Command the fuel pressure control to 180 MPa with
a scan tool. The actual fuel pressure should be the same as the commanded pressure.
‹› If the engine does not start or the fuel pressure is less than 145 MPa when commanded, replace the fuel injection pump.
15. Command the fuel pressure control to 180 MPa with a scan tool. The fuel pressure should be able to reach 145 MPa when commanded.
‹› If the fuel pressure is less than the specified value, refer to Fuel System Diagnosis. See: Computers and Control Systems/Testing and
Inspection/Component Tests and General Diagnostics
16. Operate the vehicle in order to verify the repairs.
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 Injection Pump Replacement
*
Fuel Pressure Relief Valve Replacement
*
Fuel Injector Replacement (Left) Fuel Injector Replacement (Right)
