Emission Control Components

DENSO's Emission Control(EC) Components are designed to detect and purify gasoline engine exhaust. By assessing gas temperature and oxygen concentrations, EC Components can quickly remove harmful substances, playing an essential role in improving environmental performance and fuel efficiency.


Achieving Cleaner-than-air Exhaust

A catalyst removes harmful exhaust substances most effectively when the air-to-fuel ratio is between 14.5:1 and 14.7:1. With this theoretical ratio, the fuel injected into the engine reacts (burns) optimally with oxygen. DENSO's Engine EC Components control the fuel injection volume based on data gathered from various sensors, resulting in exhaust that is cleaner than air.


  • A/F Sensor

A/F Sensor

DENSO's A/F Sensor detects the air-fuel ratio of the engine's exhaust. A vapor-liquid separation cover and water exposure protection layer provide water resistance in the exhaust pipe where water condenses. This minimizes the branch in the sensor's main unit so the element electrode can quickly detect air-fuel ratio in each cylinder. This innovative design controls fuel injection volume and reduces sensor activation time when the engine starts.

  • FLAD® Substrate

FLAD® Substrate

The Flow Adjustable Designed cell (FLAD) substrate in the exhaust pipe supports the catalyst which purifies engine exhaust. DENSO developed FLAD with a focus on the difference in exhaust flow rate and speed. In a conventional honeycomb structure, the cross-sectional area of the cells are uniform, so the amount of catalyst (which contains precious metals) in the outer portion is the same as that in the inner portion where the flow rate of exhaust is high, resulting in waste. The FLAD substrate molds a structure of different cell cross-sectional areas in the inner and outer portions to improve exhaust flow uniformity. As a result, less precious metal catalyst is used compared to conventional products.