Virtually all modern vehicles run using a computer controlled engine management system. The engine computer receives data from various sensors to regulate and adjust the fuel mixture of that engine so that the vehicle can stay running in peak condition. One of these sensors is the air charge temperature sensor, also known as the intake air temperature sensor.
This sensor measures the temperature of the air coming into the engine. As cold air is much more dense than hot air, the measurement from this sensor allows the computer to make the correct adjustments necessary for the engine to stay running smoothly under all conditions. Usually, when the air charge temperature sensor fails it will display a few symptoms that can alert the driver of a potential problem that should be inspected.
1. Lack of power when accelerating
One of the first symptoms that a vehicle will display when the air charge temperature sensor has failed is a noticeable reduction in power when accelerating. A bad or failing sensor will not send the correct signal to the computer which will negatively affect the computer’s air / fuel mixture calculations.
2. Trouble with cold starts
Another symptom of a bad or defective air charge temperature sensor is difficulty starting in cold conditions. The air charge temperature sensor sends a signal to the computer during cold conditions that allow the computer to provide additional fuel required during cold starts. A failing or defective sensor will not be able to send the correct signal to the ECU (engine control unit), which can result in increased difficulty when cold starting a vehicle.
3. Decrease in fuel efficiency
Another symptom of a bad or defective air charge temperature sensor is a noticeable decrease in fuel efficiency. The air charge temperature sensor sends data to the computer, which allows it to make continuous adjustments to the engine’s air / fuel mixture for maximum fuel efficiency. Any problems with the sensor can result in incorrect calculations by the ECU, which may result in a decrease in fuel efficiency.
The air charge temperature sensor plays an important part in the vehicle’s engine management system. Because it’s signal can impact engine performance, if you suspect that your air charge temperature sensor is failing or defective, then have a professional technician, such as one from YourMechanic, test it and if necessary replace the sensor to restore vehicle performance.
This article originally appeared on YourMechanic.com as Symptoms of a Bad or Failing Air Charge Temperature Sensor and was authored by Eduardo Ruelas.