Symptoms of a Faulty or Faulty Air Cleaner Temperature Sensor

If your vehicle is having trouble starting in cold weather, the Check Engine light is on, or idle quality is poor, you may need to replace the ACT sensor.

The air cleaner temperature (ACT) sensor plays an important role in the engine control systems of many modern vehicles. The ACT sensor senses the temperature of the air entering the engine and sends a signal to the computer so it can adjust fuel delivery and timing based on the operating conditions detected by the sensor. When the sensor starts to have problems, it can send an incorrect signal to the computer, which can adversely affect the operation of the engine, so it should be checked and replaced if necessary. When an air cleaner temperature sensor fails, the car will usually show several symptoms that can alert the driver to a potential problem.

1. Poor quality of inactivity

Poor idle quality is one of the first symptoms of an air cleaner temperature sensor problem. The ACT sensor provides a signal that is very important for the engine computer to calculate the correct idle conditions, especially during cold starts and in cold weather conditions when the density of the incoming air increases. When the sensor has problems, it can send the wrong signal to the computer, which can lead to low, rough, or jerky idling.

2. Problems with engine operation in cold conditions.

The ACT sensor detects the temperature of the air entering the engine so that the computer can make the correct calculations to achieve the best engine performance. This signal becomes even more important in cold and wet weather, as cold air is much denser than warm air. If the ACT sensor is faulty, the vehicle may have trouble idling or may stumble and misfire when accelerating after a cold start or in cold or wet weather.

3. Check Engine light comes on.

Aside from driveability symptoms, the most obvious sign of an ACT sensor problem is the Check Engine light. If the computer detects a problem with the sensor signal, the light will turn on. This is usually the last symptom as it only activates after a problem is detected. A quick scan of trouble codes will quickly show you what the problem might be.

Since the ACT sensor provides an important signal to the computer, any problems with it can quickly lead to engine performance problems. If you suspect you may have a problem with the ACT sensor or if the Check Engine light is on, contact a professional technician such as AvtoTachki to diagnose the vehicle and replace the ACT sensor if necessary.