Symptoms of A Faulty Mass Airflow Sensor

The mass airflow sensor is one of the critical components of the electronic fuel injection system of your truck. It is between the air filter and the intake manifold of the engine. In some trucks, the intake air temperature sensor is within the mass airflow sensor. 

Various types of mass airflow sensors require different types of maintenance. The digital sensors send frequency output. On the other hand, the analog mass airflow sensors produce variable voltage output. Both frequency and voltage output are sent to the engine control module that aids in regulating the air-fuel mixture.

Mass airflow sensor measures the air mass that flows into the engine intake of your truck. Such measurement is essential in calculating the necessary fuel for proper combustion in the cylinders. A faulty mass airflow sensor makes it difficult for the engine control module to calculate the fuel injection correctly. When such happens, your truck will experience various issues.

Signs of a Failing Mass Airflow Sensor

The mass airflow sensor degrades and becomes faulty with time. The degradation is because it is constantly exposed to moving air, full of exhaust fumes, dust, and debris. Such makes it too dirty to keep working flawlessly. When the mass airflow sensor is faulty, it will likely show a code B1479. And below are some of the common symptoms. 

Check Engine Light

The appearance of the check engine on your dashboard is adequate evidence that something is wrong with your mass airflow sensor. The sensor can either be faulty or dead. Consider taking your truck to a professional to determine the issue in such a scenario.

Emission of Black Smoke

The emission of black smoke is evidence of an imbalance of the air mass in your engine. When your mass airflow is faulty, your engine will receive inadequate air, leading to excess fuel burning. 

Engine Missfire

When inadequate air flows into the combustion chamber, your engine will misfire or rough. Such results from the power train control module needing to know the much-required fuel to keep your engine running. Such creates uneven combustion that leads to engine misfires.

Hard Start

An imbalance in the air-to-fuel ratio makes it difficult to start your truck. When such happens, you will experience a hard start, or sometimes your truck will not start until you fix the problem. Therefore, seeking a professional’s services is essential to fix the faulty sensor. 

Poor Fuel Economy

If you realize that the rate at which your truck consumes fuel has recently gone high, it could signal a serious issue. A faulty mass airflow could send inaccurate information to the powertrain control module, making your truck burn too much fuel.


Monitoring the air that flows to the combustion chamber is essential, enabling the engine to determine the right amount of fuel for adequate combustion. The mass airflow sensor measures the fuel flow into the engine’s combustion chamber. 

When this sensor becomes faulty, your truck will experience several issues, such as the ones discussed above. If you note any of them in your truck, take it to a professional to check and fix your mass airflow sensor.

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