OEM 2002 Buick Century Intake Manifold

2002 Buick Century Intake Manifold Parts and Q&A

• Q: How to replace the lower intake manifold on 2002 Buick Century?

  A: The process starts with disconnecting the negative battery cable before removing the upper Intake Manifold and left and right valve Rocker Arm covers and engine coolant temperature (ECT) sensor electrical connector. Remove the wiring harness for the Fuel Injector and maf sensor before taking off the clip holding the fuel pipe in place. Remove the Fuel Injector rail by first disconnecting the fuel feed pipe and fuel return pipe from the rail. Remove the Power Steering Pump while disconnecting the heater inlet pipe with heater hose along with the radiator inlet hose and Thermostat bypass hose. Lower Intake Manifold bolts must be removed along with the lower Intake Manifold itself and valve rocker arms, pushrods, and lower Intake Manifold gaskets and seals. Begin by cleaning the gasket mating surfaces and removing all rtv sealant from the lower Intake Manifold and engine block. Then proceed to remove the ect sensor, water outlet bolts, and water outlet before removing the Thermostat. For installation, start by installing the Thermostat and water outlet, tightening the water outlet bolts to 25 nm (18 ft. Lbs.) tighten the inlet ect sensing element to 23 nm (17 ft. Lbs.) torque. Apply a bead of rtv sealer gm p/n 12346286 (Canadian P/N 10953472) measuring from 8 to 12 mm (0.08 - 0.11 inch) to each ridge where the lower Intake Manifold connects to the engine block. Proceed to install the lower Intake Manifold gaskets and valve rocker arms as well as pushrods before setting the lower Intake Manifold into position. Treat the threads of modified lower Intake Manifold bolts with gm p/n 12345382 (Canadian P/N 10953489) while following the standard torque sequence: vertical bolts receive 7 nm (62 lb in) and 13 nm (115 lb in) and diagonal bolts reach 7 nm (62 lb in) and 25 nm (18 lb ft). After reinstalling the Power Steering Pump and Fuel Injector rail replace the Thermostat bypass hose before installing the radiator inlet hose and the heater inlet pipe and heater hose. Complete the installation with the fuel return pipe and fuel feed pipe. Secure the fuel pipe clip and bolt it to 8 nm (71 inch lbs.)begin by connecting the wiring harnesses for the Fuel Injector and map sensor followed by connecting the ect sensor electrical connector. After returning cable, check for leaks between all replaced components. Also reinstall the right and left valve Rocker Arm covers, upper Intake Manifold, and negative battery cable reconnection.