The exhaust emission system uses catalyst to reduce harmful elements such as hydrocarbon, carbon monoxide and nitrogen oxides in the exhaust gas. The exhaust emission system also detects the air/fuel ratio in exhaust gas using an oxygen sensor and/or air/fuel ratio sensor. It then sends signals to the engine ECU to maintain the air/fuel ratio around the stoichiometry, operating the catalyst most effectively.

DENSO’s control algorithm and sensing technologies enable the catalyst to quickly reach a temperature effective for purification immediately after the engine start, as well as effectively purify the exhaust gas under any driving conditions.