Secondary Air Injection

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 a cold start.

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





The relay is supplied with current via the +30 circuit. The pump is supplied with current from the relay via maxi fuse 1 and the air injection control valve from the relay via fuse 13. The relay is grounded via pin 37 of the control module.

This process is activated when the engine has been started if the following conditions are fulfilled:
^ coolant temperature: 1-32°C (34-90°F)
^ intake air temperature: 10-40°C (50-104°F)
^ engine speed: < 4000 rpm.

The process is activated for 72 seconds or until the temperature of the coolant reaches 40°C (104°F).