OEM 2000 Buick Century Intake Manifold

2000 Buick Century Parts Questions & Experts Answers

• Q: How to replace the lower intake manifold on 2000 Buick Century?

  A: The first step for lower Intake Manifold replacement involves disconnecting the ground cable from the battery. The replacement process begins with removal of the upper Intake Manifold followed by left and right valve Rocker Arm covers. Begin by disconnecting the wiring harness for engine coolant temperature (ECT) then proceed to disconnect Fuel Injector and manifold air pressure (MAP). Begin by removing the fuel pipe clip bolt then the fuel pipe clip before disconnecting both fuel feed and return pipes from the Fuel Injector rail. Pull out the Fuel Injector rail before relocating the Power Steering Pump from the front engine cover space. The heater inlet pipe along with the radiator inlet hose must come off followed by disconnecting the Thermostat bypass hose. Use a socket wrench to remove the bolts securing the lower Intake Manifold while also removing the manifold alongside valve rocker arms and pushrods. The procedure requires you to remove lower Intake Manifold gaskets and seals while cleaning all gasket areas on cylinder heads, engine block and lower Intake Manifold using degreaser until all traces of loose rtv sealer disappear. Begin the operation by taking out the engine coolant temperature (ECT) sensor followed by water outlet bolts and the water outlet before dealing with the Thermostat. For installation, start by installing the Thermostat and the water outlet, tightening the water outlet bolts to 25 nm (18 ft. Lbs.) install the ect sensor with a torque of 23 nm (17 ft. Lbs.). Apply an 8-12 mm (0.08-0.11 inch) bead of rtv sealer, gm p/n 12345739 or equivalent, onto each ridge that the front and rear of the lower Intake Manifold contacts the engine block before installing the lower Intake Manifold gaskets. Proceed with installing the valve rocker arms and pushrods while the lower Intake Manifold follows. Apply sealant gm p/n 12345382 to all lower Intake Manifold bolt threads then hand tighten vertical fixtures before securing new mounting bolts using torque values of 7 nm (62 lb in) and then 13 nm (115 lb in) for vertical bolts and 7 nm (62 lb in) and then 25 nm (18 lb ft) for diagonal bolts. Bypass the Thermostat hose to the radiator inlet pipe and the heater inlet pipe with heater hose to the lower Intake Manifold. Return the Power Steering Pump and Fuel Injector rail into position and unite the fuel return and feed pipes to the Fuel Injector rail. Attach the fuel pipe clip and torque the fuel pipe clip bolt to 8 nm (71 inch lbs.). Finish the installation by reattaching the Fuel Injector wiring harness with map and installing the ect wiring harness and placing right and left valve Rocker Arm covers. The final step includes installing the upper Intake Manifold and reattaching the battery ground (negative) cable.