P0172
P0172
Diagnosis information - DME V8 DFI
Lambda control adaptation bank X: system too rich
NOTE: Diagnosis should indicate a negative deviation of more than 30% (leaning) of the lambda control adaptation.
Diagnostic conditions
- Lambda control active
- Lambda control adapted
- Tank vent closed
- Engine temperature > 60 °C (140 °F)
- Intake air temperature < 80 °C (176 °F)
- Engine running > 45 seconds at engine speed < 800 rpm
- then driving at varying load ranges and engine speeds between 1,060 rpm ... 2,490 rpm
Possible fault causes
- Incorrect main filling signal from hot-film mass air flow sensor
(setpoint voltage with stopped engine and ignition on = 0.9 ... 1.1 V)
- Mechanical fault of tank vent (stuck open)
- Tank vent driver fault
- Mechanical fault of fuel injector(s) (stuck)
- Wrong fuel high-pressure signal