OEM 2003 Chevrolet Express 3500 Intake Manifold

2003 Chevrolet Express 3500 Intake Manifold Parts Questions & Experts Answers

• Q: How to replace the intake manifold on 2003 Chevrolet Express 3500?

  A: Begin the replacement process by removing the Throttle Body in addition to the oil fill tube and fuel injectors. Detach the electrical connectors for the manifold absolute pressure (MAP) sensor together with the Knock Sensor and exhaust gas recirculation (EGR) valve. Pull out the Knock Sensor harness connector before placing the electrical harness to the side. Start by removing egr pipe bolts from three locations including Intake Manifold and Cylinder Head and Exhaust Manifold and then extract the egr pipe with its gasket. First detach the positive crankcase ventilation (PCV) hose and separates the MAP Sensor along with the accelerator control cable bracket bolts and the bracket itself. Clear the evap purge solenoid vent tube by first untethering the evap tube end from the solenoid itself followed by pressing the quick connect fitting retainer then releasing the evap tube end from its connection to the vapor pipe. Securely detach the evap purge solenoid bolt while removing the isolator and Intake Manifold bolts before taking out the Intake Manifold along with its gaskets which must be discarded. Wash down the egr pipe gasket areas and Exhaust Manifold gasket surfaces if the vehicle has these components. Position new Intake Manifold gaskets onto the Intake Manifold before you proceed with the manifold installation. Treat the Intake Manifold bolt threads with threadlock gm p/n 12345382 (Canadian P/N 10953489) or equivalent product to a reserve of 5 mm (0.20 inch) and proceed with bolt installation. Tighten the bolts in sequence to 5 nm (44 inch lbs.) for the first pass and 10 nm (89 inch lbs.) for the final pass. Secure the evap purge solenoid and its isolator together using a 10 nm (89 inch lbs.) torque setting. Connect the solenoid vent tube to both solenoid and vapor pipe before installing the accelerator control cable bracket with bolts. Tighten the bolts to 10 nm (89 inch lbs.). A thin layer of clean engine oil should cover the MAP Sensor seal before sensor installation followed by installation of the pcv hose. If equipped, position a new egr pipe gasket on the Exhaust Manifold and install the egr pipe (with valve), tightening the egr pipe bolts to the Intake Manifold , cylinder head , and Exhaust Manifold to 10 nm (89 inch lbs.), 50 nm (37 ft. Lbs.), and 30 nm (22 ft. Lbs.) respectively. Terminate the electrical harness into its proper position before plugging in the Knock Sensor harness and MAP Sensor connector alongside the EGR Valve connector when equippe install the Throttle Body and fuel injectors and oil fill tube as the final steps.