9 Possible OBD DTCs Linked to Mass Airflow Sensor Issues
The MAF sensor is typically located in the air intake system between the air filter and the throttle body. It measures the mass of the air flowing into the engine and sends this information to the ECM, which calculates the correct amount of fuel to inject into the engine. The MAF sensor can fail due to a variety of reasons, such as contamination from dirt or debris, damage to the sensor or its wiring, or problems with the air intake system.
When a problem occurs with the MAF sensor, the ECM will typically set a DTC related to the issue. The specific DTC will depend on the nature of the problem, but some of the most common DTCs related to MAF sensor issues include:
P0100 – Mass or Volume Air Flow Circuit Malfunction
What happens to the car: the engine may run poorly or not at all, and the “check engine light” will illuminate.
Cause: a wiring issue, faulty connector, or a defective sensor.
Fix: inspect the wiring and connectors for damage or corrosion. Replace the sensor if necessary.
P0101 – Mass or Volume Air Flow Circuit Range/performance Problem
What happens to the car: the engine may run poorly, have reduced power and fuel efficiency, and the “check engine light” will illuminate.
Cause: a dirty or contaminated sensor, a vacuum leak, or an issue with the air intake system.
Fix: clean or replace the sensor as necessary. Inspect the air intake system for any leaks or issues.
P0102 – Mass or Volume Air Flow Circuit Low Input
What happens to the car: the engine may run poorly, have reduced power and fuel efficiency, and the “check engine light” will illuminate.
Cause: a faulty or dirty sensor, a vacuum leak, or an issue with the air intake system.
Fix: clean or replace the sensor as necessary. Inspect the air intake system for any leaks or issues.
P0103 – Mass or Volume Air Flow Circuit High Input
What happens to the car: the engine may run poorly or not at all, and the “check engine light” will illuminate.
Cause: a faulty sensor, a vacuum leak, or an issue with the air intake system.
Fix: replace the sensor if necessary. Inspect the air intake system for any leaks or issues.
P0104 – Mass or Volume Air Flow Circuit Intermittent
What happens to the car: the engine may run poorly, have reduced power and fuel efficiency, and the “check engine light” will illuminate intermittently.
Cause: a wiring issue, faulty connector, or a defective sensor.
Fix: inspect the wiring and connectors for damage or corrosion. Replace the sensor if necessary.
P0171 – System Too Lean (Bank 1) – Related to MAF Sensor Issues in Some Cases
What happens to the car: the engine may run poorly, have reduced power and fuel efficiency, and the “check engine light” will illuminate.
Cause: a dirty or contaminated sensor, a vacuum leak, an issue with the fuel delivery system, or an issue with the exhaust system.
Fix: clean or replace the sensor as necessary. Inspect the air intake system, fuel delivery system, and exhaust system for any leaks or issues.
P0172 – System Too Rich (Bank 1) – Related to MAF Sensor Issue in Some Cases
What happens to the car: the engine may run poorly, have reduced fuel efficiency, and the “check engine light” will illuminate.
Cause: a dirty or contaminated sensor, a malfunctioning fuel injector, or an issue with the fuel delivery system.
Fix: clean or replace the sensor as necessary. Inspect the fuel injectors and fuel delivery system for any issues.
P0174 – System Too Lean (Bank 2) – Related to MAF Sensor Issue in Some Cases
What happens to the car: the engine may run poorly, have reduced power and fuel efficiency, and the “check engine light” will illuminate.
Cause: a dirty or contaminated sensor, a vacuum leak, an issue with the fuel delivery system, or an issue with the exhaust system.
Fix: clean or replace the sensor as necessary. Inspect the air intake system, fuel delivery system, and exhaust system for any leaks or issues.
P0175 – System Too Rich (Bank 2):
What happens to the car: When the P0175 – System Too Rich (Bank 2) DTC appears, the engine is running excessively rich on the bank 2 cylinders. This means that there is too much fuel in the air/fuel mixture, which can cause a range of issues such as reduced fuel economy, decreased engine power, and increased emissions.
Cause: The most common cause of this DTC is a faulty mass airflow sensor (MAF) or oxygen (O2) sensor. A malfunctioning MAF sensor can cause the engine to receive incorrect readings of the amount of air entering the engine, leading to an incorrect fuel-to-air ratio. Similarly, a faulty O2 sensor can cause the engine to receive incorrect readings of the amount of oxygen in the exhaust gases, leading to an incorrect fuel-to-air ratio.
Fix: To fix this issue, the first step is to inspect and clean the MAF sensor and O2 sensors. If the sensors are dirty or contaminated, cleaning or replacing them can often resolve the issue. If the sensors are not an issue, other possible causes may include a vacuum leak or a malfunctioning fuel pressure regulator. We recommend taking the vehicle to a qualified mechanic or technician to diagnose and fix the root cause of the issue.
It is important to note that while these codes are often related to a faulty MAF sensor, there can be other causes as well, so it is important to diagnose the root cause of the issue before replacing any parts. Additionally, in some cases, a faulty MAF sensor may not trigger any codes, so it is important to keep an eye out for any symptoms such as reduced power, poor fuel economy, or rough idle, and have the system inspected if necessary.