P0104moderate severityPowertrain
Mass Air Flow (MAF) Circuit Intermittent
on 2012 Subaru Impreza 2.0L H4 · AWD
What this code means
The MAF sensor signal is intermittent, showing erratic readings.
Symptoms
- Check Engine Light (intermittent)
- Intermittent stalling
- Surging
- Poor driveability
Common causes
- Loose MAF connector
- Damaged wiring
- Intermittent sensor failure
- Vibration-induced disconnect
Diagnostic steps
- Wiggle test on MAF connector
- Inspect wiring for chafing
- Monitor MAF signal for dropouts
- Check connector pins
Repair notes
Repair connector or wiring. Replace sensor if internal failure.
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