GM 12638990
Exhaust Manifold, Passenger Side

The powertrain replacement is the first step for right Exhaust Manifold replacement. The first step involves disconnecting the bolt which joins the catalytic converter pipe to the bell housing followed by removing the connector position assurance lock from the Oxygen Sensor and extracting both Oxygen Sensor electrical connectors (1, 2). After completing Oxygen Sensor removal the worker should proceed to extract the right Exhaust Manifold heat shield bolts while taking out the heat shield. Take out the Exhaust Manifold bolts first before you remove the Exhaust Manifold with its old gasket which should be discarded. The installation procedure requires the application of thread-lock gm p/n 12345493 (Canadian P/N 10953488) or equivalent on a 5 mm (0.2 in) wide section across Exhaust Manifold bolts and studs threads. Place the Exhaust Manifold onto the block using a new gasket and use a wrench to tighten the center bolts first then alternate between each bolt to reach 25 n.m (18 lb ft). Fasten the Exhaust Manifold while also tightening the exhaust hanger bolt to 50 n.m (37 lb ft). The installation of the right Exhaust Manifold heat shield along with its bolts requires 10 n.m (89 lb in) torque force. Cover all Oxygen Sensor threads with gm p/n 12377953 anti-sieze compound or an equivalent compound before installing the oxygen sensors which need to be tightened to 42 n.m (30 lb ft). Fasten the electrical connectors of the Oxygen Sensor before locking in the cpa components. Finally, reinstall the powertrain.

Ensure the cylinder head exhaust manifold bolt hole threads are clean.

Remove the oxygen sensors, followed by the left exhaust manifold heat shield bolts and the heat shield.

Secure the exhaust manifold and catalytic converter bolt to the bell housing, tightening the exhaust hanger bolt to 50 Nm (37 lb ft).

Tighten them to 42 Nm (30 lb ft).