P2193

P2193

Lambda control adaptation in upper load range, bank 2 (FRAO2) - above limit value

Diagnostic conditions - V8
- Battery voltage between 10 V and 16 V
- Lambda control active
- Engine temperature > 60 °C
- Mass air flow > 320 Kg/h
- Engine load for naturally aspirated engine > 26.3%
- Engine load for turbo engine > 82.5%

Diagnostic conditions - V6
- Battery voltage between 10 V and 16 V
- Lambda control active
- Engine temperature > 60 °C
- Mass air flow > 240 Kg/h
- Engine load > 24%

Possible fault cause
- Hot-film mass air flow sensor 1 and / or 2 faulty (setpoint voltage with stopped engine and ignition on = 0.9 to 1.1 V) --> see Actual values, Filter [[DME mass air flow]], [[Mass air flow 1 (sensor)]] + [[Mass air flow 2 (sensor)]]
- Fuel pressure too low
- Fuel pump delivery too low
- Mechanical fault in fuel injector (stuck)
- Incorrect main filling signal

Affected pins
DME control unit plug A, pin 29, and pin 5 of hot-film mass air flow sensor 1
Not V6 - DME control unit plug B, pin 109, and pin 5 of hot-film mass air flow sensor 2

Diagnosis/fault finding

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

Hint:
V8 only - If this fault is set, both hot-film mass air flow sensors must always be tested because the main filing signal is calculated from both signals.