P0103 on BMW
Mass or Volume Air Flow Circuit High Input
P0103 on BMW vehicles indicates mass or volume air flow circuit high input. Au7o has documented this code across 1 BMW model — most commonly on M5. This generic code means the PCM detected a higher-than-expected signal voltage or airflow reading from the mass air flow (MAF) sensor circuit. Because the MAF reading directly affects fuel delivery, an abnormally high signal can cause the engine to run rich or behave erratically, with symptoms like rough running, hesitation, or poor fuel economy. It typically points to a sensor or wiring problem, or unmetered conditions confusing the sensor. Typical repair costs on BMW range from $300 to $900, depending on the specific model and root cause.
Common Causes of P0103
- •Faulty or contaminated mass air flow sensor
- •Short to voltage in the MAF signal wiring
- •Damaged connector or corroded terminals at the MAF
- •Intake/vacuum leak affecting the signal
- •Dirty MAF sensor element
- •Poor sensor ground
- •Faulty PCM (rare)
P0103 on BMW by Model
BMW M5(1 issue)
- MAF Sensor Degradation Causing Lean Codes, Hesitation, and Reduced Power2000-2003
The S62 uses dual mass-airflow sensors, and aging or contaminated MAFs are a recurring E39 M5 issue. Owners commonly report rough idle, hesitation, poor throttle response, reduced power, and check-engine lights with mixture adaptation faults. BMW service literature and independent repair databases frequently reference diagnosis of intake leaks versus faulty MAF readings on E39 V8 applications.
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View P0103 across all makes →Frequently Asked Questions
What does P0103 mean on BMW?▼
P0103 stands for "Mass or Volume Air Flow Circuit High Input." This generic code means the PCM detected a higher-than-expected signal voltage or airflow reading from the mass air flow (MAF) sensor circuit. Because the MAF reading directly affects fuel delivery, an abnormally high signal can cause the engine to run rich or behave erratically, with symptoms like rough running, hesitation, or poor fuel economy. It typically points to a sensor or wiring problem, or unmetered conditions confusing the sensor. On BMW specifically, this code is documented across 1 model.
What causes P0103 on BMW vehicles?▼
Common causes on BMW: Faulty or contaminated mass air flow sensor, Short to voltage in the MAF signal wiring, Damaged connector or corroded terminals at the MAF, Intake/vacuum leak affecting the signal, Dirty MAF sensor element. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0103 on a BMW?▼
Repair costs on BMW range from $300 to $900, depending on the specific model and root cause.
Which BMW models have P0103 documented?▼
Au7o has documented P0103 on 1 BMW model: M5.