Remove the air cleaner assembly and the preheat ducting between the exhaust manifold and the air cleaner. Take out the EFI throttle cable bracket bolt, the dipstick tube bracket bolt, and the ground strap bolt. Raise the vehicle and support it securely on jackstands, then remove the catalytic converter splash shield. Disconnect the exhaust pipe-to-exhaust manifold flange bolts, applying penetrating oil if they are corroded. If necessary, support the exhaust system with a piece of wire; if all mounting springs are intact, additional support may not be needed. Disconnect the oxygen sensor connector wire from its retaining clip and the electrical connector from the wire harness, noting that removal of the sensor from the manifold is only necessary if replacing the manifold. Label and disconnect the four spark plug wires, setting them aside. Loosen and remove the exhaust manifold retaining bolts and washers, starting with the end ones and then the middle ones, using penetrating oil if needed. Remove the exhaust manifold and gasket from the engine, ensuring the oil dipstick tube is pushed back into the block before reinstalling the manifold. Clean the gasket mating surfaces on the cylinder head and the exhaust manifold with a wire brush to remove all leftover gasket material and carbon deposits. Place a new exhaust manifold gasket on the cylinder head, position the manifold, and install the mounting bolts finger tight. The exhaust bolts are numbered from 1 to 7; tighten them gradually in the sequence 3-5-6-2-1-7-4 to the specified torque. Reattach the four spark plug wires and reconnect the oxygen sensor lead wire to the wire harness. Install a new exhaust manifold flange gasket between the exhaust manifold and the exhaust pipe, then tighten the exhaust manifold-to-exhaust pipe flange bolts. Reinstall the catalytic converter splash shield and tighten it securely, followed by the EFI throttle cable bracket. Finally, install the preheat ducting between the exhaust manifold and the air cleaner, then reinstall the air cleaner assembly. Start the engine and check for exhaust leaks between the exhaust manifold and cylinder head as well as between the exhaust manifold and the exhaust pipe.
