Today’s vehicles are complex and computerized. Sensors located in your exhaust, braking, vehicle fluids, temperature, and other systems alert your vehicle computer when a part or system is working improperly.
When a sensor detects a problem you will often see your check engine light, oil pressure gauge, temperature, or other dash light will appear warning you of an engine problem.
Some common vehicle sensors include:
- Oxygen Sensor, is designed to keep engine performance and efficiency at peak levels at all times while also keeping emissions in check. The O2 sensor is part of the emission control system located in the exhaust pipe, and monitors the gases leaving the engine to ensure the correct amount of oxygen is reaching the combustion chamber. A gasoline-powered engine relies on a precise ratio of air and fuel to burn efficiently, and following combustion, the sensor detects how much un burned oxygen is present in the exhaust gases to determine if the mixture was too rich or too lean and adjust accordingly.
- ABS Sensor (ABS) A wheel speed sensor, also called, “ABS sensor” is part of the Anti-lock Brake System (ABS). It is located on the tires (near the brake rotors for the front tires and in the rear end housing for the rear tires). The job of the wheel speed sensor is to constantly monitor and report the rotational speed of each tire to the ABS control module. ABS is a safety system that prevents your car from skidding or sliding when you apply the brakes. When the brake is applied, the ABS control module reads the speed data from the speed sensor and sends the correct pressure to each wheel to prevent any sliding/skidding (wheels locking up).
- Mass Air Flow Sensor, used to find out the mass of air entering a fuel-injected internal combustion engine. The air mass information is necessary for the engine control unit (ECU) to balance and deliver the correct fuel mass to the engine. Air changes its density as it expands and contracts with temperature and pressure.
- Oil Pressure Sensor, As the oil is circulated by the automotive oil pump it is passed through an engine oil pressure sensor, this checks the pressure is within the manufacturer’s recommended limits and sends a signal to the oil pressure gauge warning light on the dashboard to notify the driver there is a problem.
- Tire Pressure Sensor (TPMS) If you drive a newer car, you probably have what’s called a Tire Pressure Monitoring System (TPMS) installed. TPMS is an electronic system inside the tire that monitors the air pressure in your tires. If your tires are under- or over-inflated, the TPMS activates a warning light on your dashboard. When the light is steady, it means you need to have your tire pressure checked. When the light is flashing, it means you need to have your TPMS checked.
- Throttle Position Sensor (TPS), For a car to run smoothly, it needs the proper mixture of air and fuel. The amount of air in the engine is controlled by the air intake system. A throttle body is part of the air intake system that helps control the amount of air that gets into the engine. The throttle body has a throttle plate. If the plate is closed, it prevents the air from getting into the engine. When you push the gas pedal, it opens the plate, allowing the air to enter the engine. The amount of air depends on the position of the plate, which is controlled by the gas pedal. The harder you push the gas pedal, the wider the plate will open, and more air will flow to the engine. This means more power and more speed.The throttle position sensor reports the position of the gas pedal to the computer in your car (Engine Control Unit). The computer then determines the position of the throttle plate. It also calculates the amount of air flow to the engine and the amount of fuel to be injected for the required ratio of air-fuel mixture.
- Vehicle Speed Sensor, Vehicle Speed Sensors come in several different designs depending on the manufacturer. They are used as sensor input for the ABS and Traction Control vehicle computerized systems. This sensor inputs data to the transmission for shift control, cruise control for desired operation, ABS (anti-lock brakes).
- Engine Coolant Temperature Sensor, the temperature gauge will let you know when your car’s engine temperature begins to exceed normal ranges. Unlike with most gas gauges, when engine temperature gauges begin to edge into the red, it is NOT wise to keep driving another five miles!