Automotive Computers and Sensors

When you’re driving along in your car, truck or SUV the last thing you want to see is that bright “Check Engine” light which indicates that you have a problem with the computer in your vehicle. The check engine light is very vague and can be a number of things are wrong in the system. If the light does come on you don’t need to call for a tow, but do get it checked out as soon as possible so you don't encounter future complications.

The light is included in the OBD or onboard diagnostics system. The computer inside the vehicle regulates and monitors factors such as the RPMs, timing of the ignition and how the fuel gets mixed. If any problems are found in the engine control module or ecm, the light will turn on to alert the driver that a problem has been detected. It is very generic and doesn’t pinpoint the exact cause or source of the problem, but does give a warning sign.

The ecm receives signals from the vehicle’s various sensors. The oxygen sensor measures how much oxygen is in the exhaust system and alerts the computer to how much fuel is in the gas tank. A bad sensor negatively impacts the vehicle’s gas mileage because the malfunctioning sends the wrong information to the computer.

It’s also possible that the mass air flow sensor is bad if your check engine light suddenly comes on. It is responsible for measuring how much air is getting to the engine so it knows how much fuel is necessary. The mass air flow sensor is a costly repair and can run several hundred dollars to replace, but not fixing it creates a lack of power in the vehicle, a surge when accelerating and poor fuel economy. The engine coolant temp sensor may also cause the check engine light to turn on. Its job is to measure the temperature of the coolant. If any readings are irregular, it sends of signals that something is wrong and should be fixed as soon as possible.

Other issues that may also cause the check engine light to come on such as a loose gas cap because it allows the fumes to escape or problems with the spark plugs and/or the wires. The spark plugs have the job of igniting the air fuel mixture in the engine. If they misfire, the power and fuel economy of the engine are negative effected and can also create and cause damage to the catalytic converter. If the problem is not immediately addressed, it can turn a relatively inexpensive repair into one that costs hundreds of dollars.

Don’t allow your vehicle to go without proper attention and repair. If the check engine light comes on take the vehicle to a mechanic who will be able to diagnose and fix the problem before it escalates.