Disconnect the cable from the negative terminal of the battery. Block the rear wheels, set the parking brake, raise the front of the vehicle and support it securely on jackstands. Disconnect the downstream oxygen sensor connectors. Remove the engine middle splash shield. Unbolt the exhaust pipes at the exhaust manifolds. Lower the vehicle. Working in the engine compartment, disconnect the oxygen sensor's electrical connector. If removing the right exhaust manifold, detach the EGR pipe from the top of the manifold. If removing the left manifold, remove the air filter housing and the engine oil dipstick tube. Remove the exhaust manifold upper heat shield mounting bolts and remove the heat shields. Remove the mounting bolts and detach the manifold from the
Cylinder Head. Be sure to spray penetrating lubricant onto the bolts and threads before attempting to remove them. Clean the mating surfaces to remove all traces of old gasket material, then inspect the manifold for distortion and cracks. Warpage can be checked with a precision straightedge held against the mating flange. If a feeler gauge thicker than 0.030-inch can be inserted between the straightedge and flange surface, take the manifold to an automotive machine shop for resurfacing. Place the exhaust manifold in position with a new gasket and the lower heat shields and install the mounting bolts finger tight. Starting in the middle and working out toward the ends, tighten the mounting bolts in several increments, to the torque. Install the remaining components in the reverse order of removal. Start the engine and check for exhaust leaks between the manifold and cylinder head and between the manifold and exhaust pipe.