Air Injection: Description and Operation

The secondary air system consists of an air injection pump which blows air into the two exhaust manifolds via a vacuum-controlled valve. The purpose of this is to make the three way catalytic converter start working as soon as possible after starting from cold.

The supplementary air starts a chemical reaction with unburned and partially burnt fuel (HC and CO), thus generating heat.

This process is activated when the engine has been started if, the following conditions are fulfilled:
^ coolant temperature: 1-39°C (34-102°F)
^ intake air temperature: 1-39°C (34-102°F)
^ engine speed: <4000 rpm.

The process is activated for 64s or until the temperature of the coolant reaches 47°C (117°F).





The pump relay is supplied with current (+30 circuit) via fuse 3 and grounded from pin 37 of the control module.

The secondary air injection control valve is supplied with current (+15 circuit) via fuse 19 and grounded from pin 62 of the control module.