In the past, you could just turn a screw to do an engine tune-up. The engines of today are far more complex, utilizing numerous computers and sensors that communicate with each other to tell the main computer what exactly is happening with the car. While some sensors are as simple as the one measuring your windscreen washing fluid, others measure the temperature of incoming air, the air-fuel mixture in your gas tank, the speed of your wheels, and even something like the pressure of the manifold.
How to read your check engine light codes: If you truly consider how much use your vehicle gets, especially in the case of a daily driver style, it’s amazing that the sensors of the car don’t wear out faster. Anything else subjected to the kind of wear and tear we put our vehicles through would surely give out much sooner. This means that the sensors of the car can corrode, wear out, or just become dirty. When this happens, it can send faulty information to the main computer, and this is what can trigger the unwanted check engine light. The codes that these throws are easy enough to figure out with the right equipment, however. A code reader is an inexpensive tool that can help you figure out the meaning of the code, and where an error has occurred in communication. Most auto parts stores are also happy to read the codes for you, knowing that you’ll probably opt to come in and buy the parts necessary to fix it. Whether you’re a grease monkey or not, you probably know one, and it will probably cost you less than a true trip to a mechanic’s garage.
There are two different sets of code information, specific to the manufacturing years of cars. If your car was built pre 1996, the code reader will have to be able to read OBD I information. If built after 1996, then the reader needs to be able to read OBD II codes. Also keep in mind that before you replace a sensor, you might have to do some deducing to find out the true problem. This goes back to how all of the sensors communicate with the main computer. A dirty sensor could be hiding an underlying problem. Utilize a code reader and the manual of the vehicle for the best results.
What are the most common sensors?
On the extreme end, bad sensors can cause so much confusion for the computer that the engine of the car could fail. While this isn’t a common occurrence (unless sensors are routinely ignored), at the very least, your vehicle isn’t running at optimum settings, which can affect things like basic performance and even gas mileage. Some of the most common sensors to cause issues are below:
IAC, the idle air control valve: Helps to regulate how much air enters the engine when it sits at an idle, and typically located on the body of the throttle.
MAP, the manifold absolute pressure sensor: This check for any variations in the air pressure coming into the engine. The main computer reads the variations to deliver the proper amount of spark and fuel.
IAT, the intake air temperature sensor: This is the sensor to aid the computer in regulating exhaust gas recirculation, dealing in producing cleaner tailpipe emissions.
O2, oxygen sensor: This is located near the stream of exhaust produced by the vehicle, and keeps track of the composition of the air leaving the engine. It is an important part of the chain for emissions control, and it helps the main computer determine correct fuel mixture and the best fuel delivery. When this sensor fails, it tends to cause a richer running condition and tailpipe smoke that is quite dark, even black.
Learning about the sensors should be one of the first lessons about your car. It isn’t enough to simply drive the car between places. You should know how to listen to what it is saying to know the maintenance and care it requires.