Exhaust System: Notes

The purpose of the exhaust system is to convey engine emissions from exhaust manifold to atmosphere. Engine exhaust emissions are directed from engine exhaust manifold to catalytic converter through front exhaust pipe. A Heated Oxygen Sensor (HO2S) is mounted on the front exhaust pipe before catalyst. Catalytic converter reduces concentration of Carbon Monoxide (CO), unburned Hydrocarbons (HCs) and Oxides of Nitrogen (NOx) in exhaust emissions to an acceptable level. Reduced exhaust emissions are directed from catalytic converter to a muffler through rear exhaust pipe. Another HO2S is mounted on rear exhaust pipe. Exhaust emissions are then directed to atmosphere through an exhaust tailpipe.