Ideally, before performing any operation, turn off the car by detaching the cable of the negative terminal of the battery. Disconnect the exhaust manifold oxygen sensor electrical connecter and if replacing with a new one, then remove the sensor also. Subsequent to this, unbolt the heat shield bolts on the manifold and fit the helped of heat shield away. Spray penetrating oil on the exhaust manifold bolts/nuts and also on the exhaust pipe nuts. Lift the car and put it on lifter jacks and then pull of the engine splash shields. Remove exhaust flange nuts, and supporting bracket bolts along with nut of catalytic converter flange Finally untwine the exhaust pipe from manifold and the catalytic converter and then lower the vehicle. Loosen and take off the manifold nuts and separate the manifold from the
Cylinder Head using penetrating oil if the nuts are tightly fixed, let them to soak for 15mins before you continue. If any bolts or studs break during removal, they can be removed using the locking pliers when the manifold is off, and for the broken stud, you could purchase the stud removal tools at any automotive store. Any part that is damaged should be replaced with the factory part or a part belonging to the exhaust system. For installation, all filthy deposits and all gasket material must first be scraped off using a scraper from the mating surfaces of the manifold and cylinder head but extra caution should be taken not to mar the aluminum cylinder head. Place a new exhaust manifold gasket over the studs on the cylinder head; then, place the exhaust manifold over it and screw in the nuts. Secure the nuts from the center in the outward direction with the intended torque; reassemble the other parts in the opposite direction. If the oxygen sensor is to be reinstalled, use special anti-seize thread lubricant. Last, turn on the engine and look for exhaust heater noise.