Posts Tagged: secondary air injection system

Why carmakers install a secondary air injection system

What is a secondary air injection system A secondary air injection system is part of a vehicle’s emission system. It’s used to reduce emissions during cold starts when the engine is running on a rich fuel mixture to overcome the cold quenching effect of cold combustion cylinders. Unfortunately, the rich fuel mixture doesn’t burn completely causing some of the unburned fuel to exit with the exhaust and flow into the catalytic converter. The catalytic converter is responsible for burning off the excess fuel, but first it must reach a “light … Read More