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Catalytic converter heating ignition

Catalytic converter heating ignition


The ignition is retarded in order to heat the catalytic converter as soon as possible after starting.

The ignition retardation together with an increase in idling speed will increase the exhaust temperature and consequently, the catalytic converter will heat much faster. This function is active on starting when the engine coolant temperature is between -10°C and 64°C, otherwise there will be no ignition retardation.

There is an ignition matrix in the control module that is added to the idling ignition or normal ignition if the catalytic converter heating function is active.

At low engine coolant temperatures, the function will be active for up to 3000 combustions and at high engine coolant temperatures down to 1000 combustions at 64°C.

The ignition retardation is dependent on load and engine speed with a typical ignition timing of around 10° after top dead centre (ATDC).