P0102moderate severityPowertrain
Mass Air Flow (MAF) Circuit Low Input
on 1999 BMW 528iT E39 2.8L I6 M52 Touring · RWD
What this code means
The MAF sensor signal voltage is lower than the minimum expected value.
Symptoms
- Check Engine Light
- Loss of power
- Rich fuel condition
- Black smoke
Common causes
- Faulty MAF sensor
- Short in signal wire
- Disconnected sensor
- Contaminated sensor element
Diagnostic steps
- Check MAF sensor connector
- Test signal voltage
- Inspect wiring for shorts to ground
- Test sensor output
Repair notes
Replace MAF sensor or repair wiring.
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29CC
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29CD
Misfire Cylinder 2
29CE
Misfire Cylinder 3
29CF
Misfire Cylinder 4
29D0
Misfire Cylinder 5
29D1
Misfire Cylinder 6
29D2
Misfire Cylinder 7
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Lambda Additive/Idle Adaptation Limit, Bank 1
29E1
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29E2
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