Q: How to replace the upper intake manifold on 2001 GMC Savana 3500?
A: To replace the upper Intake Manifold, start by disconnecting the battery negative cable, followed by the removal of the engine cover and air cleaner intake duct. Remove the fuel injector electrical connector, manifold absolute pressure (MAP) sensor, evap canister purge solenoid valve line, idle air control (IAC) solenoid, and throttle position (TP) sensor. In case there is one, install the vacuum brake booster hose and the PCV tube by rotating it to lock the ends in place. Remove the left side Spark Plug Wires from the Distributor Cap, pull the fuel pipes from the back side of the engine, and remove the air bypass hose assembly if applicable. Pry off the check valve cover on the evap canister, then drain the fuel line. Remove the evap canister fixed to the fuel tank mounting flange. Take the evaporative emission control seal ring off the fuel tank neck. Disconnect the fuel fill and vapor delivery hoses from the fuel tank. Then remove the fuel tank neck from the frame. Disconnect the fuel tank electrical connector for the fuel pump relay or the vapor pressure sensor. Unbolt the upper Intake Manifold bolts, then unbolt the upper Intake Manifold and clean all sealing surfaces on both parts. For installation, position the upper Intake Manifold on the engine, but tighten the studs on the first pass to 12 nm (44 inch lbs.) and the second pass to 10 nm (89 inch lbs.). Connect the accelerator control cable bracket to the Throttle Body and lower Intake Manifold, securing with bolts and nut to 12 nm (106 inch lbs). Reconnect the accelerator control cable and cruise control cable to the throttle shaft, install the evap canister purge solenoid valve, and reconnect the fuel pipes to the rear of the engine. Connect the Spark Plug Wires to the left side of the Distributor Cap and install them in the correct order, and install the air bypass hose assembly if one exists. Replace the PCV tube onto the section of the Intake Manifold by twisting until it locks, plug in the vacuum brake booster hose (if it is present), then install the fuel injector electrical connector, MAP sensor, evap canister purge solenoid valve, IAC solenoid, and TP sensor. Finally, replace the air cleaner intake duct, engine cover, and reattach the battery negative cable.