To remove the left exhaust manifold, first, remove the oil dipstick tube bracket from the engine and, on models manufactured after 1997 remove the exhaust gauge air (EGA) tube from the exhaust manifold, and the EGA valve. If the power steering pump hoses interfere with manifold removal, unbolt the hoses from the pump; put caps on the fittings to keep dirt out; and move the hoses clear of the way. Again for the right exhaust manifold, remove the heater hose bracket and relieve the pressure from the heater hoses. Third, one needs to remove the exhaust pipe from the manifold(s) that might include using a wrench to loosen up the exhaust pipe nuts, hence may involve lifting the car and placing it on stands to access the exhaust pipe joints. Make sure, if the vehicle has Automatic Ride Control, the air suspension switch is off before lifting the vehicle to prevent the damage of system components. Take out all the bolts and then proceed to take off the exhaust manifold off from the cylinder head. During installation assemble the exhaust system cleaning the mating surfaces on the cylinder head, and exhaust manifold as well as exhaust pipe with a scraper and solvent. Spread graphite grease on the cylinder head mating surface, fit the manifold to it and tighten the bolts taking care to apply equal force so that they are tightened to the correct quantity of torque. Most of these engines can be assemble without the exhaust manifold gaskets, provided the mated surfaces are flat and in good condition; warped or damaged manifolds may require a gasket or re-surfacing which are available locally from auto parts stores. After that you ought to join the exhaust nipple to the exhaust manifold and the nuts should be tightened up to the recommended torque. Other steps of installation are the reverse of the removal and if its heater hoses were disconnected then fill the cooling system. Last of all, start the engine and look for exhaust noted leakages.
