ME-SFI lambda control, function - GF07.61-P-4022AM
ENGINE 113.990 in MODEL 211, 219
ENGINE 113.991 in MODEL 215, 220
ENGINE 113.992 in MODEL 230 up to Model Year 2008
ENGINE 113.993 in MODEL 463 up to 31.5.12
ENGINE 113.995 in MODEL 230 up to Model Year 2008
The mixture composition is controlled within the narrowest possible limits around λ = 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 λ=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 O2 sensor voltage drops and the ME control unit compensates for this lean drift through a matching enrichment.
This makes it possible to achieve a fuel-air mixture of approximately λ = 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.
| Fuel injection valve, location/task/design/function | GF07.03-P-5004KE | ||
| O2 sensors, location/task/design/function | GF07.04-P-4103AM | ||
| Crankshaft position sensor, location/task/design/function | GF07.04-P-4116AM | ||
| Pressure sensor, location/task/design/function | GF07.04-P-5014AM | ||
| Coolant temperature sensor, location/task/design/function | GF07.04-P-5026AM | ||
| Charge air temperature sensor, location/task/design/function | GF07.04-P-5039AM | ||
| ME-SFI control unit, location/task/design/function | GF07.61-P-5000AM | ||
| Accelerator pedal sensor, location/task/design/function | GF30.20-P-4010HA | ||
| Three-way catalytic converter, location/task/design/function | GF49.10-P-3002AM |