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Secondary air injection(SE only)

Secondary air injection (SE only)


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

About five seconds after the engine fires, the secondary air injection pump starts and a solenoid valve opens the passage leading to the exhaust manifolds.

Since this process is dependent on both time and temperature, the solenoid valve closes and the pump stops either when a maximum of 80 seconds has elapsed or when engine temperature reaches 65°C, whichever occurs first.

At an engine temperature of 20°C (68°F) the pump runs for about 80 seconds.

The pump will start only if the temperature of both the intake air and the coolant is between +1°C and +35°C (33°F - 95°F).