P0103 Mass air flow sensor A circuit high
What P0103 means
The signal from the mass air flow sensor is above the range the engine computer considers possible. The computer cannot trust the reading and switches to estimated airflow, which makes fuelling less accurate.
P0103 is a generic SAE J2012 code: it means the same on every make. The exact cause still depends on the car, so read the freeze-frame data before replacing parts.
At a glance
- Severity
- High
- Typical repair cost
- 40–350 €
- Workshop time
- 0.3–1.5 h
- Repair difficulty
- Easy
- DIY possible
- Yes
- Check engine light
- Yes
- Affects emissions test
- Yes
Parts and labour at an independent workshop in Europe. Main dealers charge more; the cause decides the bill, not the code.
Symptoms
- Check engine light on
- Rough running or hesitation
- Black smoke or rich running
- Stalling or poor idle
- Possible reduced power
Common causes
- Failed MAF sensor
- Signal wire shorted to a voltage source
- Poor ground connection at the sensor
- Incorrect or poor-quality replacement sensor
- Electrical interference from nearby aftermarket wiring
Can I keep driving with P0103?
Get it checked within a few days. The engine runs on substitute values and may run rich, stall or hesitate.
What to check first
- Check the MAF connector and wiring for damage, chafing against other wires and corrosion.
- Measure the sensor ground: a poor ground often raises the signal voltage.
- Unplug the sensor with the key on and check whether the signal reading drops; if it stays high, the signal wire is shorted.
- If the wiring is good, replace the MAF sensor with a correct part.
Related codes
- P0102 Mass air flow (MAF) sensor A circuit low
- P0104 Mass air flow sensor A circuit intermittent
- P0101 Mass air flow sensor A range/performance
- P0105 Manifold absolute pressure / barometric pressure sensor circuit
- P0100 Mass air flow sensor A circuit
- P0106 Manifold absolute pressure / barometric pressure sensor range/performance
- P0107 Manifold absolute pressure / barometric pressure sensor circuit low
- P0108 Manifold absolute pressure / barometric pressure sensor circuit high
Data: TORKO fault-code catalogue, built on OBDex (CC0-1.0) and reviewed against workshop practice. Informational only — it does not replace a diagnosis by a mechanic.
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