P0103 Code: Mass Air Flow Sensor Circuit High
🟠 Moderate severity · drivable
The car usually still runs, but you may see poor fuel economy, rough running, and possibly black exhaust smoke.
What P0103 means
The mass air flow (MAF) sensor measures incoming air so the engine computer can set the fuel mixture. This code means the sensor signal is higher than it should be. The engine may run rich, use too much fuel, and run poorly.
Symptoms
- Check engine light on
- Poor fuel economy
- Engine runs rich or rough
- Black smoke from the exhaust
- Fouled spark plugs over time
Common causes
- most common: Faulty MAF sensor
- common: Wiring shorted to power in the MAF circuit
- less common: Dirty or contaminated sensor element
- less common: Poor ground connection
How to fix it
| Fix | DIY? | Typical cost |
|---|---|---|
| Replace the MAF sensor | Yes | $80–250 |
| Repair the MAF wiring short to power | Yes | $20–80 |
| Clean the MAF sensor element | Yes | $10–20 |
| Repair the sensor ground circuit | Yes | $10–50 |
Frequently asked questions
Can I drive with P0103?
Short trips are okay, but the engine runs rich and uses more fuel. Over time that can foul spark plugs and damage the catalytic converter.
What does a high MAF signal mean?
The sensor is reporting more airflow than the engine actually gets. A bad sensor or a wire touching power usually causes this.
Can I clean the MAF sensor instead of replacing it?
Cleaning is worth trying, but a high-voltage fault is more often a failed sensor or a wiring problem.
Related codes
P0101
P0101 Code: Mass or Volume Air Flow (MAF) Sensor Circuit Range/Performance
P0102P0102 Code: Mass Air Flow Sensor Circuit Low
P0172P0172 Code: System Too Rich (Bank 1)
Updated 2026-08. This page is informational and not a substitute for professional diagnosis.