Q: How to replace the lower intake manifold on 2001 Chevrolet Express 3500?
A: When replacing the lower Intake Manifold, first remove the battery negative cable and drain the engine coolant. It also involves removing the air cleaner intake duct, engine shelter, and Coolant Reservoir, upper Radiator Hose, inlet heater hose, outlet heater hose, and coolant by-pass hose. Switch off the scpi injector electrical connector, manifold absolute pressure (MAP) sensor, evap canister purge solenoid valve, idle air control (IAC) motor, throttle position (TP) sensor, exhaust gas recirculation (EGR) valve, and engine coolant temperature (ECT) sensor. Remove the air bypass hose assembly if available, and use a twisting motion to disconnect the Brake Booster Vacuum Hose. Then, unplug the Distributor, fuel pipes from the rear of the engine basket, accelerator control cable, and cruise control cables from the throttle shaft, accelerator control cable bracket from the Throttle Body and lower Intake Manifold, ignition coil, an ecm bracket, and wake control of egr tube from Intake Manifold. It is also notable that discharging the a/c refrigerant is unnecessary. If available, remove the air conditioning (A/C) compressor and place it aside, then the mounting bracket for the power steering pulley and the left and right side valve rocker arm covers. Lastly, take out the lower Intake Manifold and dry all the sealing surfaces. For installation, the lower Intake Manifold should me placed on the engine, followed by placing the left and right side valve rocker arm covers and power steering pump mounting bracket and A/C Compressor if, equip. Connect the egr pipe via the bracket and front of the Intake Manifold, ignition coil and ecm bracket. If available, install the air bypass hose assembly, then install the accelerator control cable bracket to the Throttle Body and lower Intake Manifold, and the accelerator control cable and cruise control cable to the throttle shaft. Install the fuel pipes, distributor, and pcv tube to the Intake Manifold using a twisting motion to lock it. If available, you should attach the vacuum brake booster hose, then connect the scpi injector electrical connector, map sensor, evap canister purge solenoid valve, iac motor, tp sensor, egr valve, and ect sensor. Reassemble the air bypass hose assembly and Brake Booster Vacuum Hose if equipped, the upper Radiator Hose, inlet heater hose, outlet heater hose, coolant bypass hose, coolant reservoir, engine cover, and air cleaner assembly, respectively. Refill the engine coolant and connect the negative cable of the battery.