P1099

P1099

Diagnosis information - DME V8 DFI

Mass air flow in front of throttle (MAF2) implausible

NOTE: For this fault code, the intake system between the hot-film mass air flow sensor and the throttle is monitored.

NOTE: A mass air flow is calculated from the signals from the throttle potentiometer, engine speed sensor, intake air temperature sensor and ambient pressure sensor and compared with that measured via MAF2 sensor.

Diagnostic conditions
- Vehicle voltage > 9 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 sensor fault

Possible fault causes
- Hot-film mass air flow sensor 2 faulty (displaced characteristic)
(setpoint voltage with stopped engine and ignition on = 0.9 ... 1.1 V
- see Actual values, Filter [MAF], [Mass air flow 1 (sensor)])
- Air flow onto hot-film mass air flow sensor deflected