Mass Airflow (MAF) Sensor Problems and Symptoms

What the MAF sensor does

The mass airflow sensor measures the air flowing into the engine and sends that information to the engine computer. The computer uses it to set the right fuel mixture (injector pulse width) for performance, emissions and fuel economy.

Symptoms of a bad MAF sensor

• Rough idle
• Hesitation or jerking when accelerating
• Loss of power
• Poor fuel economy
• Stalling
• A check engine light with codes related to airflow or oxygen sensors

It may not be the sensor

The same symptoms and codes can come from a vacuum leak, a torn intake duct between the MAF sensor and the throttle body, a blocked intake or worn wiring. A contaminated sensor is also common. Cleaning is sometimes an option, but only after diagnosis. That is why we test before replacing parts.

Keeping it healthy

Replace the air filter on the schedule in your owner’s manual and make sure it is installed correctly, since dirt that gets past it can coat the sensor.

Next step

Our ASE-certified technicians can inspect your vehicle and explain your options. Book at whichever of our shops is most convenient.