GM 91177110
Exhaust Manifold

The first step before working on the 2.0l Exhaust Manifold replacement requires waiting for the exhaust system to cool down since it remains hot. Vehicles with pup Catalytic Converter need three bolts and two nuts for Exhaust Manifold heat shield detachment followed by three nuts that separate the front pipe assembly from the Exhaust Manifold along with engine mount bracket and Exhaust Manifold bracket from the engine block. When working on vehicles without pup catalytic converters you should start by removing the 4 bolts and 1 nut from the heat shield followed by raising the vehicle and then using the twc bolts to detach the front pipe assembly. After lowering the vehicle you need to remove the Exhaust Manifold-to-engine block bracket. The technician must remove the Oxygen Sensor from the Exhaust Manifold after disconnecting its electrical connector. Caretakers should first extract the single bolt and eight nuts from the Exhaust Manifold while also taking out the Exhaust Manifold along with its engine lift hook and cylinder head gasket. Install a new Exhaust Manifold Gasket on the cylinder head before attaching the Exhaust Manifold along with the engine lift hook and tightening the 8 nuts and 1 bolt to 50 nm (37 ft. Lbs.). After installing a new gasket between the Exhaust Manifold and lower Exhaust Pipe secure them with three 50 nm (37 ft. Lbs.) torque sealed nuts. The Exhaust Manifold heat shield requires three bolts and two nuts when installed. First use the same procedures to install the gasket and manifold but then lift the vehicle and position the front pipe assembly with a new seal connected through twc bolts tightened to 50 nm (37 ft. Lbs.) afterward lower the vehicle before securing the Exhaust Manifold-to-engine block bracket and the heat shield with 4 bolts and 1 nut. Obtain anti-seize compound for the Oxygen Sensor threads and tighten it to 45 nm (33 ft. Lbs.) before connecting the Oxygen Sensor electrical connector. Finish the inspection process by checking for gas leakages within the exhaust system.

Disconnect the negative battery cable and the heated oxygen sensor (HO2S1) electrical connector.

Secure it with 2 bolts tightened to 50 Nm (37 ft. lbs.).