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P1100

P1100

Mass air flow ahead of throttle valve (MAF2) implausible (too high)

Diagnostic conditions
- Battery voltage between 10 V and 16 V
- Engine running
- No electrical MAF2 sensor fault
- No throttle valve adjusting unit fault
- No ambient pressure sensor fault
- No intake air temperature sensor fault
- No speed sender fault

Possible fault cause
- Hot-film mass air flow sensor 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)<<
- Throttle valve stiff or >>blocked<<
- Throttle valve adjusting unit faulty
- Intake air temperature sensor faulty (in hot-film mass air flow sensor)

Affected terminals
-

Diagnosis/fault finding

Hint:
- For this fault code, the intake system between the hot-film mass air flow sensor and the throttle valve is monitored.
- A mass air flow is calculated from the signals from the throttle valve potentiometer, engine speed sender, intake air temperature sensor and ambient pressure sensor and compared with that measured via MAF2 sensor.