Air Injection: Description and Operation

Secondary Air Injection
- Secondary air injection has been added to the M44 engine to enable it to comply with TLEV standards. It is an output control function of the M5.2 engine control system. The operation of the Air Injection system is similar to the MS 41.1 system used on the 2.8 liter engine.

The system consists of the following components:
^ Secondary Air injection
Electric Motor/Pump
^ Motor Pump Relay
^ Vacuum Vent Valve (solenoid)
^ Non-Return Valve
^ Secondary Air injection Pipes





Secondary Air Injection Control
The parameters for air injection operation are as follows:
^ Below -10°C, the injection pump is activated briefly to blow out any accumulated moisture and prevent it from freezing.
^ Between -10°C and 40°C, the air injection pump is switched on, on start up, for of 2 minutes.

Secondary Air Injection Monitoring
- Component operation of the air injection pump and vacuum vent valve are monitored by the M5.2 control module. The system checks the operation of the system by monitoring the final stage control in the control module.