OEM Buick Terraza Intake Manifold

Buick Terraza Intake Manifold Parts and Q&A

• Intake Plenum
  12604753
  Q: How to replace the lower intake manifold on Buick Terraza?

  A:

  First, take the negative black cable (ground) off the battery before attempting to replace the lower Intake Manifold. The upper Intake Manifold, valve Rocker Arm covers, and the engine coolant temperature (ECT), Fuel Injector, and manifold air pressure (MAP) wiring-harnesses should be removed. Then, you have to pull out the Fuel Injector rail and, take off the heater inlet pipe with heater hose from the lower Intake Manifold and move it to its position. To do this remove the radiator inlet hose from the engine and remove the water outlet along with the Thermostat. Go ahead and take out the lower Intake Manifold bolts and the lower Intake Manifold before the valve rocker arms and pushrods. Take the lower Intake Manifold gaskets and seals off, clean the upper gasket and seal surfaces of the cylinder heads and the engine block as well as of the lower intake, use degreaser, to remove all loose room temperature vulcanizing sealer (RTV). Put the gaskets of the lower Intake Manifold in place, followed by the rocker arms for the valve and pushrods. Install a small drop of t rtv sealer gm p/n 12378521 (Canadian P/N 88901148) at the joints at the Intake Manifold's four corners, then install lower Intake Manifold. Replace now with new fasteners and ensure that there is a screw-lock patch on them or thread-locking chemical on the old fasteners to maximize the gasket performance. Tighten the lower Intake Manifold bolts in sequence to 13 nm (115 inch lbs.) for the first pass, then to 20 nm (15 ft. Lbs.) for bolts (1, 2, 3, 4) and 25n (18 ft. Lbs.) for bolts (5,6,7,8) on final pass. Retighten the heater inlet pipe and the nut until it reaches 25 nm (18 ft. Lbs.), and then install the Thermostat and water outlet bolts. Install the ect sensor with a 20 nm (15 ft. Lb.) torque and aanther the Thermostat bypass hose with the Thermostat bypass pipe and the lower Intake Manifold pipe. Reattach the radiator inlet hose, heater inlet pipe, and heater hose to the lower Intake Manifold. Mount the Power Steering Pump on the front engine cover, fuel injector rail, then connect the fuel feed pipe to the Fuel Injector rail. Put together the Fuel Injector and map wiring harness, ect wiring harness, and both valve Rocker Arm covers. Lastly, install the upper Intake Manifold and reconnect the negative cable of the battery ground.