GM 91177111 Engine Exhaust Manifold (On Esn)

You can Select Your Vehicle to check if 91177111 fits your vehicle.

Disconnect the negative cable from the battery. Set the parking brake and block the rear wheels. Raise the front of the vehicle and support it securely on jackstands. Unplug the oxygen sensor connector. Remove the exhaust manifold heat shield bolts or nuts and then remove the heat shield. Remove the exhaust manifold flange nuts/bolt. Apply penetrating oil to the threads of the exhaust pipe studs to make removal easier. Apply penetrating oil to the threads of the exhaust manifold mounting studs, and then remove the exhaust manifold mounting nuts. Slip the manifold off the studs and remove it from the engine compartment. Remove and discard the old gasket. Clean and inspect all threaded fasteners and repair as necessary. Remove all traces of gasket material from the mating surfaces and inspect them for wear and cracks. Install a new gasket, install the manifold and tighten the nuts in several stages, working from the center out, to the torque. Reinstall the remaining parts in the reverse order of removal. Run the engine and check for exhaust leaks.

Slip the manifold off the studs and remove it from the engine compartment.