OEM 2008 Chevrolet Silverado 1500 Intake Manifold

2008 Chevrolet Silverado 1500 Parts Questions & Experts Answers

• Q: How to replace the upper intake manifold on 2008 Chevrolet Silverado 1500?

  A: To dismantle upper Intake Manifold, start with the fuel pipes/ hoses. Eliminate the a/c pressure switch, and the a/c compressor clutch if available, and the control port injector module. Unbuckle the engine wiring harness clips (1, 2), unbolt the rear bracket and then unplug the evap canister purge solenoid valve and manifold absolute pressure (MAP) sensor. Remove evap canister purge solenoid valve tube quick connect fitting and relocate the tube. Remove the ground nut and wire off the rear of the right c ylinder head and remove the stud that supports the engine wiring harness bracket, and put the harness out of the way. Unplug the PCV Valve Hose, the power Brake Booster Vacuum Hose, and the upper Intake Manifold - upper studs. Remove the Intake Manifold - upper, throwing the gasket and o-ring seal from the fuel meter body. If needed, when removing the Throttle Body and its gasket and you have to turn off the power brake booster vacuum fitting, the o-ring seal and the pcv valve cover, as well as the rear Throttle Body stud. If necessary, unbolt the MAP Sensor and its seal and the evap canister purge solenoid valve studs in order to access the purge solenoid valve. Clean and inspect the Intake Manifold-upper as necessary. For installation, if opted for, install the purge solenoid valve and the evap canister purge solenoid valve studs with threadlock if you are intending to reuse the old studs, then tighten them to 10 n.m (89 lb in). Should you need so, fit a new MAP Sensor seal with a drop of clean engine oil then fit the MAP Sensor. Replace the Throttle Body Gasket if necessary, then the Throttle Body and the rear Throttle Body stud with applying threadlock if using the old stud and tightening it to 9 n.m (0.80lb in). Replace the pcv cover with a new o-ring seal using clean engine oil, thereafter the pcv valve cover. Replace a fuel meter body new o-ring seal and a new upper Intake Manifold gasket before putting the upper Intake Manifold. If reusing old Throttle Body/Intake Manifold studs, apply threadlock and install the front two Throttle Body studs and the Intake Manifold - upper studs with 9 n.m (80 lb in). Replace the power Brake Booster Vacuum Hose and the PCV Valve Hose back to the valve cover and rocker cover. Mount the engine wiring harness and bracket and attach engine wiring harness bracket stud and tighten it to 25 n.m (18 lb ft). Install the engine wiring harness rear bracket nut to the evap canister purge solenoid valve into 9 n.m (80 lb in) and the engine wiring harness ground nut and wire to the rear of the right cylinder head into 16 n.m (12 lb ft). Connect the evap canister purge solenoid tube quick connect fitting to evap purge solenoid valve then that of evap canister purge solenoid valve and MAP Sensor. When you are done, place the engine wiring harness rear bracket to the upper Intake Manifold and secure it using bolts with the bolt torque of 10 n.m (89 lb in). Install the engine wiring harness clips(1, 2) to the engine harness brackets and attach the control port injector module and at last reconnect the a/c compressor clutch and the a/c pressure switch if installed, before you install the fuel pipes/hoses.