Overheating/pinging protection - function - GF07.61-P-4027BK

ENGINE 113.967 in MODEL 219 

ENGINE 113.964 in MODEL 164.1 up to Model Year 8 

ENGINE 113.971 in MODEL 251 up to Model Year 8 

Fig 1: Overheating/Pinging Protection Function Diagram

Courtesy of MERCEDES-BENZ USA

The task of the overheating/pinging protection is to prevent engine damage as a result of excessive thermal overload and overheating damage of the catalytic converters.

The heat quantity given off by the cooling system into the environment is mainly dependent on the fan speed, vehicle speed, outside temperature and Coolant temperature. In order to avoid exceeding the maximum permissible Coolant temperature it is necessary, to limit the heat brought into the cooling system from combustion and thus the engine performance.

This is achieved by ensuring that the throttle valve is no longer opened fully. The air mass drops accordingly and less fuel in injected.