P1094

P1094

Diagnosis Information - DME (DFI)

Implausible mass air flow ahead of throttle valve

NOTE:
- The fault P1094 Implausible mass air flow ahead of throttle valve valve indicates that a mass air flow deviation from the calculated model has been detected between the hot-film mass air flow (MAF) sensor and the throttle valve in at least one load range.
- An initial indication appears because the corresponding fault(s) is/are stored.
- A mass air flow is calculated from the signals from the throttle potentiometer, engine speed sensor, intake air temperature sensor and ambient pressure sensor as well as other engine operating values.
- The calculated mass air flow is compared with that measured by the mass air flow (MAF) sensors.
- Any deviation may be due to both the calculated mass air flow and the measured mass air flow.
- A throttle valve for which forced adaptation was carried out under the wrong conditions (e.g. intake air temperature > 40 °C (104 °F)) can result in the fault entry.
- It is possible to establish in the extended fault memory whether the adaptation process is responsible for the fault entry.
- To do this, you must exit guided fault finding.
see fault memory for fault code P1094 under
- [F8]
- [F5] ENVIRONMENTAL CONDITIONS
- Environmental conditions when fault first occurred
- Environment 6 (last entry):
- Value X means that forced adaptation of the throttle valve was performed under the wrong conditions.
- Value Y means that forced adaptation of the throttle valve was performed under the right conditions.

Diagnostic conditions
- Throttle valve was adapted under the right conditions
(including: intake air temperature < 40 °C (104 °F))
- Engine running
- No electrical fault for hot-film mass air flow sensor (MAF)
- No throttle valve adjusting unit fault
- No ambient pressure sensor fault
- No intake air temperature sensor fault
- No speed sensor fault
- No valve lift fault
- No camshaft adjustment fault
- No intake manifold switch-over fault

Possible fault causes
- Forced adaptation of the throttle valve was performed under the wrong conditions
(e.g.: intake air temperature > 40 °C (104 °F))
- Fault in the area of valve lift, camshaft adjustment, intake manifold, intake manifold switch-over, throttle valve, ambient pressure sensor, intake air temperature sensor, speed sensor
- Changed air flow to hot-film mass air flow (MAF) sensor due to:
- Foreign matter ahead of hot-film mass air flow (MAF) sensor
- Twisted hot-film mass air flow (MAF) sensor
- Leak just ahead of hot-film mass air flow (MAF) sensor
- Clogged air cleaners
- Exhaust system faulty - flow severely restricted
- Leakage between hot film mass air flow (MAF) sensor and throttle valve adjusting unit
- Plug connection on the hot-film mass air flow (MAF) sensor oxidized / faulty.
- Hot-film mass air flow (MAF) sensor soiled/faulty (displaced characteristic)