Exhaust System

Courtesy of VOLVO CARS CORPORATION

HINT: The illustration displays the exhaust system for the XC90. 

The three-way catalytic converters clean by oxidizing carbon monoxide (CO) and hydrocarbons (HC) to water and carbon dioxide (CO₂ ). Nitrous oxides (NO_x ) are reduced to nitrogen and water. The catalytic converter transforms over 98 percent of these substances during normal operation. Lead contaminates in the fuel can damage the catalytic converter, quickly rendering it inoperable.