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  • Writer's pictureBilly Hillmuth

What is an Air Charge Temperature Sensor?

Updated: Aug 6, 2021

Most cars on the road today are run by a computer-controlled engine management system. The computer gets data from sensors throughout the vehicle in order to regulate your engine’s fuel mixture. This regulation is key to your vehicle running at its top performance and condition.

One of the many sensors among the inner workings of your car’s engine system is the air charge sensor. What does an air charge sensor do? It detects changes in air temperature. Since cold air is denser than hot air, the sensor is able to detect when the air coming into the engine is not ideal for proper vehicle performance. In turn, the sensor alerts the engine’s computer to make adjustments to the airflow as necessary.

Here are a few signs that your car’s air charge sensor may have failed:

Symptom #1 – A Change in Fuel Efficiency

One of the first signs your air charge sensor is failing is a sudden decrease in fuel efficiency. The sensor enables the computer to regulate the engine’s air-fuel mixture in order to keep fuel efficiency high. A failed air charge sensor can cause inaccurate calculations as read by the electronic control unit (ECU), thus decreasing fuel efficiency.

Symptom #2 – A Change in Acceleration

When you press the accelerator, the vehicle should begin to move forward and speed up at a pace dependent on how hard you press it. If you ever press the accelerator and notice a reduction in power, your air charge sensor may have failed. A failed sensor is unable to send the correct signal to the computer, negatively affecting its air-fuel mixture calculations.

Symptom #3 – Difficulty with Cold Starts

When it’s cold outside, your car’s air charge sensor is responsible for letting the computer know it needs to supply additional fuel in order to start and run the vehicle properly. A bad sensor will be unable to send the necessary alert to the ECU, resulting in the engine turning over but not starting.

If you believe your air charge sensor has gone bad, look to your local Maryland mechanic to get the problem solved so your engine can go back to running smoothly and efficiently.

Hillmuth Auto Care has four convenient locations throughout Maryland and offers affordable diagnostics testing, same-day service, and lasting repairs that help extend the life of your vehicle.

Contact us today for more information on the services we offer.

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