Exploring The Different Types Of Car Sensors

7 May 2015
 Categories: , Blog


Every time you use your car to do a simple task, like going to the store for milk, do you think about what is really happening? You turn the key, step on the gas pedal and five minutes later, there you are. What is going on under the hood and how does your car know what it should be doing? Your car has a multitude of sensors which tell it these things. Almost everyone knows what the speedometer does, but what does a MAP sensor do and how is it different from a MAF sensor?

Where are Your Sensors?

Sensors are generally divided by where they are in your car or by their function. There are temperature sensors, sensors which are located in the air intake and exhaust systems, and sensors which tell the car the positions of various parts. Temperature sensors are the easiest to explain—they ensure the car is not getting too hot. If it does, the sensor will first start the engine-cooling fan. If the temperature keeps rising, it alerts you by activating a warning light. The main temperature sensor is located on the engine block.

Airflow is Important

The sensors which are in your car's intake and exhaust include the Mass Air Flow (MAF) sensor and the Manifold Absolute Pressure (MAP) sensor. These two sensors detect the amount of air coming into your engine and the amount of work which is being done by your car respectively. As more work is done, the intake vacuum pressure drops, so this is a signal your car needs more air flow. Working in tandem with these is the O2 sensor on the exhaust side. If there is too much oxygen in the exhaust, it sends a signal your engine needs less air. All three working in harmony keep your gas mileage optimal.

Position is also Important

Positional sensors are used by the engine's computer to determine where the crankshaft and the camshaft are at any given moment. The camshaft sensor monitors where the first cylinder is so the sequential fuel injectors can operate correctly. The crankshaft sensor works in tandem by determining where the shaft is so that the spark plugs fire correctly. These sensors eliminate any maladjustments from wear on a timing belt or chain. Working correctly, they optimize your gas mileage as well.

Sensors in your car are put there so you get the most value for your dollar. A malfunctioning sensor will cost you more in the end than just the initial cost of replacement. If your gas mileage suddenly drops or you notice your engine is not running as well as it used to, one of the sensors could need replaced. Have your car looked at by an auto repair shop like Duncan Tire & Auto so you can get back on the road safely.