Lambda Control Adaptation Frau (Lower Load Range) - Above Limit Value

P2179

Diagnosis information - DME

Lambda control adaptation FRAU (lower load range) - above limit value

NOTE: Diagnosis should indicate a positive deviation of more than 30% (enrichment) of the lambda control adaptation in the partial load range (FRAU > 1.3).

Diagnostic conditions
- Engine load 15 .. 80%
- Mass air flow via hot-film mass air flow sensor 40 ... 220 kg/h
- Engine speed 1,040 ... 4,760 rpm
- Lambda control ahead of catalytic converter active
- Engine temperature > 55.5 °C (132 °F)
- No tank ventilation
- USA: Time after engine starts 250 ... 350 seconds
- RoW: Time after engine starts 302 ... 402 seconds
- No faults detected for oxygen sensor
- No faults detected for tank vent
- No faults detected for hot-film mass air flow sensor

Possible fault causes
- Hot-film mass air flow sensor faulty (displaced characteristic/soiled, e.g. due to faulty air cleaner/unfiltered air)
(setpoint voltage with stopped engine and ignition on = 0.9 ... 1.1 V
- see Actual values, Filter > Mass air flow [, ] Mass air flow sensor 1 (sensor) [ + for Turbo ] Mass air flow sensor 2 (sensor) < )
- Intake system leaking (secondary air)
- Leak in exhaust system
- Fuel pressure too low
- Fuel injector faulty (stuck)
- Fuel pump delivery too low