OEM 2008 Chevrolet Impala Intake Manifold

2008 Chevrolet Impala Parts Questions & Experts Answers

• Q: How to replace the lower intake manifold on 2008 Chevrolet Impala?

  A: Before replacing the lower Intake Manifold, you must take off the ground negative cable from the battery. Remove the upper Intake Manifold, then the left and right valve rockerarm covers. Unplug the fuel feed line from the Fuel Rail and the Fuel Injector inline connector, remove the Fuel Injector harness connector bracket bolt, and remove the engine coolant temperature (ECT) and the camshaft position (CMP) sensor electrical connectors. Next, you remove both the Fuel Injector rail and its bolts along with the Fuel Rail and after that, you remove the lower Intake Manifold bolts as well as the lower Intake Manifold. Relieve the tension on the valve Rocker Arm bolts and leave the valve train components in a rack to hold the original place. Remove the valve rocker arms and push rods and pay attention that the intake push rod equal 147.51mm (5.81in) and the exhaust push rod equal 154.87mm (6.1 in). Pull off the lower Intake Manifold gaskets and seals and clean the sides of the cylinder heads and engine block, as well as the lower Intake Manifold, using a degreaser and making sure that all loose rtv (room temperature vulcanizing) sealer is removed. Install the new lower Intake Manifold gaskets and seals, put the prelube on the ends of the push rods and install them in their original locations. Treat the friction surface of the Rocker Arm with prelube, and if necessary, apply shims (P/N 88894006) under the valve Rocker Arm pedestals. Assemble the valve rocker arms and also tighten the bolts with a torque of 34 n.m (25 lb ft). Once the new gaskets and seals are installed, apply a small droplet of rtv sealer to the four corner of the Intake Manifold to the engine block joints and install the lower Intake Manifold. Before installing the lower Intake Manifold bolts, apply sealer on the lower Intake Manifold bolt threads and install the lower Intake Manifold bolts while following the suggested sequence. From the first to 16 n.m (12 lb ft) and further to 25 n.m (18 lb ft). Check the Fuel Rail, fuel injectors and fuel injectors o-rings for damage, lubricate the o-rings with engine oil, and insert the injector nozzles into the lower Intake Manifold injector bore. Press the injector rail until the injectors are fully seated, then give and install the Fuel Injector rail bolts to 10n.m (89lb in). Now connect the cmp sensor and the ect electrical connectors, align the Fuel Injector harness connector to the Intake Manifold and then install the bracket bolt with a minimum torque of 8 n.m (71 lb in). Connect the inline connector of the Fuel Injector and the fuel feed line to the Fuel Rail. Lastly, install the right and left valve Rocker Arm covers, the upper Intake Manifold and reconnect the battery ground wars.