How to Install Headers in a 1994 Honda Civic
- 1). Allow the vehicle to cool for at least 2 hours so the exhaust is cool to the touch. Pop the hood. Locate the exhaust manifold, which is directly behind the radiator, with a yellow oil dipstick in the center of it. Remove the dipstick by pulling it toward you. Unbolt the heat shield around the exhaust manifold using the 3/8-inch ratchet and socket.
- 2). Locate the oxygen sensor, which is on the passenger side of the exhaust manifold and has an electrical connection plugged in at one end. Unplug the harness using your hands, then remove the sensor using the 3/8-inch ratchet and an oxygen sensor socket.
- 3). Unbolt the top of the exhaust manifold from the cylinder head using the open-end wrench. Lift up the front of the car using the jack and put it down on jack stands. Unbolt the lower section of the exhaust manifold from the exhaust using the 3/8-inch ratchet, extension and sockets. Remove the exhaust manifold from the engine bay, and pull off the exhaust manifold gasket.
- 4). Slide the header into the engine compartment. Place the gasket between the cylinder head and the header, then loosely bolt the header onto the cylinder head with your hands. Apply a thin coating of the anti-seize compound to the threads of the oxygen sensor. Install the sensor into the header using the 3/8-inch ratchet and oxygen sensor socket, then plug the sensor into the harness.
- 5). Bolt the bottom of the header to the existing exhaust system using the 3/8-inch ratchet, extension and sockets. Tighten up the header bolts at the top of the intake manifold using an open-end wrench.
- 6). Lower the car off the stands using the jack. Turn on the car and listen at the cylinder head and at the bottom of the car for any exhaust leaks. If you hear any, tighten up the connections using the appropriate tool.
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