P0103: Mass Air Flow MAF Circuit High

P0103 is a diagnostic trouble code for vehicles equipped with a MAF sensor. The mass air flow sensor measures the air being sucked into the engine and sends that information to the ECU or PCM so the computer can ensure proper fuel delivery.

When you see this code, it means there is a problem with the measurement and it’s reading too high of conditions. Therefore, the mass air flow sensor sends a frequency to the ECU that is out of the normal range.

Related OBD-II Codes: P0100, P0101, P0102, P0104. Misfire codes and O2 sensor codes are also commonly present due to the way these systems work together to make your vehicle run. A faulty MAF sensor can cause a misfire when your computer doesn’t get the proper reading.

Don’t forget the ECU or PCM is responsible for taking the reading and using it to supply the proper amount of fuel to your engine.


  • Engine running rough
  • Check-engine light
  • Stalling
  • Black smoke coming from exhaust
  • Engine stalling immediately after starting

How to Fix P0103 Error Code

Use your OBD-II scanner to clear the code and then turn off the car. Open the hood and get ready to look at the intake system of your vehicle.

Recommended OBDII Reader: SEEKONE SK860 OBD2 Scanner

Find the engine filter housing, and follow the intake all the way to the engine. Inspect everything on the intake, looking for anything cracked, loose or damaged. Find the MAF sensor, it will be connected to the intake. Inspect the wiring going to the sensor to make sure nothing is damaged.

Start the car and run it to see if the code returns.

If the check-engine light comes back and/or the code returns when you scan it, then it’s time to remove the MAF sensor. Check to see if it’s dirty. If so, clean it with MAF sensor cleaner. Clear the code, start the car, and see if it comes back.

Recommended MAF sensor cleaner: CRC Mass Air Flow Sensor Cleaner

Once you’ve cleaned the MAF sensor and inspected the entire intake system from the filter to the throttle-body – it’s time to test the MAF sensor. Start the car, and then unplug the MAF sensor from the wiring harness while it’s still running.

If the car shuts off upon disconnecting the sensor, then it’s working properly. If the car stays running, then the sensor is no longer working properly and needs to be replaced.