GF07.61-P-4022AM ME-SFI Lambda Control, Function

GF07.61-P-4022AM ME-SFI Lambda Control, Function

Component Identification:

The mixture composition is controlled within the narrowest possible limits around lambda= 1 in order to achieve a high conversion of the exhaust gases (exhaust gas conversion) in the catalytic converters.

The O2 sensors upstream of TWC react to the oxygen share in the exhaust and transmits a corresponding voltage signal to the ME control unit. The ME control unit in turn alters the mixture composition by regulating the injection quantity in such a way that lambda=1. This process is repeated constantly (control loop).

The lambda closed-loop control is operational in the following operating conditions (closed-loop control):
^ Coolant temperature >52 °C
^ O2 sensors have reached operating temperature
^ Engine idling or partial-load range
^ Deceleration fuel shutoff not active.

The ME control unit alters the mixture composition with a time delay in order to prevent any risk of jerking.







Example:
Assuming a leaner fuel-air mixture is produced. This has the following consequence, that the O sensor voltage drops and the ME control 2 unit compensates for this lean drift through a matching enrichment.
This makes it possible to achieve a fuel-air mixture of approximately lambda= 1.
The reading of the lambda control factor with the STAR DIAGNOSIS moves towards +25% The more the lambda control factor moves in the direction +25%, the leaner is the fuel-air mixture and the greater is the enrichment of the mixture on the part of the ME control unit.