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Secondary air injection

Secondary air injection


To get the three way catalytic converter working as soon as possible after a cold start, ambient air is pumped into the exhaust manifold where the oxygen in the air starts a chemical reaction together with CO and HC pollutants, thus generating heat.

This process is activated when the engine has been started if the following conditions are fulfilled:


• Coolant temperature -1-40 °C (30-104 °F).

• engine speed < 4000 rpm


The process is activated for 55 seconds or until the temperature of the coolant reaches 40°C (104°F).