Exhaust manifold gaskets may be made of embossed steel, sometimes in multiple layers. These gaskets may also be made of high-temperature fibre material, graphite, and ceramic composites, among others. Some gaskets use a combination of different materials. Other types of exhaust gaskets include flange gaskets and ring gaskets located at various connection points in the exhaust system. These gaskets are usually made from the same types of materials as exhaust manifold gaskets.
An exhaust manifold gasket seals the exhaust manifold to the cylinder head. On V6 and V8 engines, there are two exhaust manifolds and therefore require two manifold gaskets. An exhaust manifold gasket seals the connection between the manifold and cylinder head. This prevents exhaust leakage out of the connection and also ensures that all exhaust gas will flow through the catalytic converter for treatment. Flange and ring gaskets seal other connection points in the exhaust system, such as between the exhaust pipe and exhaust manifold.
Have your vehicle's exhaust system inspected periodically to keep your car safe. Exhaust gas, especially carbon monoxide, can be deadly if it enters the interior of the car. The symptoms of an exhaust leak may include a louder than normal exhaust sound, the sound of exhaust coming from unusual places on your car, a “ticking” noise when accelerating, and the smell of exhaust. However, don't rely on your sense of smell as a conclusive means of determining if there's an exhaust leak. Carbon monoxide has no odour. If you suspect any problem with the exhaust system, have it inspected immediately by a professional technician. Another symptom of a potential exhaust leak is a failed emissions test. A leak not only lets exhaust gas out, it also allows oxygen to enter the exhaust stream, which can be detected during an emissions test. You will usually be required to make repairs before retesting, so have the leak checked by a professional technician.