OEM 2001 Buick Century Intake Manifold

2001 Buick Century Parts Questions & Experts Answers

• Q: How to replace the lower intake manifold on 2001 Buick Century?

  A: The replacement of a lower Intake Manifold begins with disconnecting the battery ground cable followed by upper Intake Manifold removal and both valve Rocker Arm cover removal. Start by disconnecting the engine coolant temperature (ECT) wiring harness then disconnect the Fuel Injector and manifold air pressure (MAP) wiring harness and finally unfasten the fuel pipe clip bolt and clip assembly. First remove the Fuel Injector rail by disconnecting the fuel feed and return pipes that connect to it. Start by moving the Power Steering Pump to a new position before disconnecting the heater inlet pipe and removing the radiator inlet hose along with disconnecting the Thermostat bypass hose. Start the procedure by taking out the lower Intake Manifold bolts followed by extraction of the lower Intake Manifold and valve rocker arms and pushrods. Also extract the lower Intake Manifold gaskets and seals. Use gm p/n 12346139 (Canadian P/N 10953463) and degreaser to clean all gasket-mating surfaces while removing all loose rtv sealer. The first step involves removing the engine coolant temperature (ECT) sensor, water outlet bolts, water outlet and Thermostat from the system. For installation, start by installing the Thermostat and water outlet, tightening the water outlet bolts to 25 nm (18 ft. Lbs.) the ect sensor requires torque application of 23 nm (17 ft. Lbs.) during installation. All gasket-mating surfaces must be cleaned before installing the lower Intake Manifold gaskets and applying rtv sealer gm p/n 12346141 (Canadian P/N 89022195) to the Intake Manifold block joint. Mount the valve rocker arms and pushrods after installing the lower Intake Manifold using new bolts. The vertical bolts securing the lower Intake Manifold should be torqued first to 7 nm (62 lb in) and then to 13 nm (115 lb in) while diagonal bolts require a torque of 7 nm (62 lb in) first followed by 25 nm (18 lb ft). Reconnect the Thermostat bypass hose together with the radiator inlet hose and heater inlet pipe while tightening the heater inlet pipe nut to 25 nm (18 lb. Ft.). After reinstalling the Power Steering Pump add the Fuel Injector rail assembly by using gm p/n 12345616 (Canadian P/N 993182) o-rings on the injectors and push them fully into the lower Intake Manifold. Reinstall the Fuel Injector rail assembly while using gm p/n 12345616 and canadian p/n 993182 o-ring seals and fully press each injector into the lower Intake Manifold. Tighten the rail bolts to 10 nm (89 lb in) before reinstalling the fuel return and feed pipes and their clip and bolt which must be secured with 8 nm (71 inch lbs). You should finish by reconnecting the Fuel Injector and map wiring harness along with the ect wiring harness before reinstalling both valve Rocker Arm covers and upper Intake Manifold and connecting the battery ground cable.