Operation CHARM: Car repair manuals for everyone.

GF07.61-P-4027KE Overheating/Pinging Protection, Function



GF07.61-P-4027KE Overheating/Pinging Protection, Function
- up to model year 08

Component Identification:






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

If the coolant temperature/charge air temperature is too high, the ignition timing point is retarded in line with engine speed and load. The correction by retarding the ignition timing is map-controlled by the ME control unit.

The retardation of the ignition timing point commences at a coolant temperature of approx. 90 °C and a charge air temperature of approx. 20 °C.

The ignition timing is retarded e.g.:
- at 100 °C coolant, 20 °C charge air and full load 2° crank angle
- at 100 °C coolant, 60 °C charge air and full load 8° crank angle
- at 125 °C coolant, 60 °C charge air and full load 11° crank angle

The following information is processed in the ME control unit for this purpose:
^ Engine speed and crankshaft position
^ Intake manifold pressure and air mass
^ Intake/charge air temperature
^ Coolant temperature
^ Throttle valve position

The ignition angle corrections of the coolant temperature, intake/ charge air temperature and knock control are added in line with the performance map.