GF07.61-P-3032KE ME-SFI Catalytic Converter Heating-Up, Function

GF07.61-P-3032KE ME-SFI Catalytic Converter Heating-up, Function
- up to model year 08

Component Identification:

The heating-up of the TWC is designed to heat up the catalytic converters more rapidly to its operating temperature and thus to sharply reduce the exhaust gas emissions at cold start.

The following sub-systems are involved:
^ Ignition system -> In the idle speed range and in line with the coolant temperature the ignition angle is retarded for e.g. 20 seconds in order to increase the exhaust gas temperature.
^ Idle speed control -> Dependent on coolant temperature, the idle speed is increased to approx. 1100 to 1300 rpm for up to 20 seconds.
^ Transmission shift delay (with transmission 722) -> Depending on the coolant temperature, the automatic transmission is upshifted with a delay.
^ Air injection -> the enriched fuel-air mixture after start and in the warming-up phase contains many more uncombusted hydrocarbons in the exhaust. The injected air (after burning) causes post-oxidation in the catalytic converters.