4 Cylinder EZA

Engine output torque reduction is a function of both the EZA and DME control modules. The EZA control module makes the determination that power reduction is required and the DME carries out the request for torque reduction. The major difference with the EZA system is the elimination of the throttle control for torque reduction.





Retarding the ignition timing is the main control request utilized by the EZA for reducing the engine's output torque.

Additionally, the control module can request DME to selectively cancel fuel injectors to further reduce the power output if required.





There are limits to retarding the timing based on the exhaust gas temperature in front of the catalytic converter. If the temperature goes too high, damage can result to the catalytic converter.





The exhaust gas temperature in front of the catalytic converter is calculated by the EZA control module based on the intake air temperature, engine temperature and ignition timing.

This temperature factor is taken into account when the processor determines that power reduction is called for. If the calculated temperature is below the threshold limit, the EZA will call for retarding the timing to reduce the output power.





If the calculated temperature is to high, the EZA will go the an acceptable limit on timing retard and selectively cancel injectors to reduce the power.

In practical application, the EZA uses a combination of retarded timing and cylinder shut down to bring the wheel slip under control.