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Catalytic converter heating ignition

Catalytic converter heating ignition


In order to heat the catalytic converter as quickly as possible after starting, the ignition will be retarded.

This ignition retardation together with an increase in idling speed causes the exhaust temperature to rise, which in turn heats the catalytic converter much faster. The function is active during start when the coolant temperature is between -10°C and 64°C. There will be no ignition retardation outside this range.

The control module contains and ignition matrix that is added to the idling ignition timing or normal timing if the catalytic converter heating function is active.

The function will be active for up to 5000 combustions at low coolant temperatures and at high coolant temperatures down to 1000 combustions for short periods at 64°C.

Ignition retardation is dependent on load and engine speed with a typical ignition timing of around 10° ATDC.