A vehicle's check engine light (or "service engine soon" light) usually indicates a problem with the ignition, fuel, transmission, or exhaust system. Often, it comes on for one of the following problems below:
Gas Cap
This is the easiest and quickest fix, which is why most people hope that is why their engine light came on. When you forget to screw your gas cap all the way, or it is damaged, your car will detect a “leak”. The cap is supposed to keep the fuel vacuum sealed.
Spark Plugs
Worn spark plugs or plug wires can initiate the check engine light. These are necessary to ignite the engine. If they’re over 100K miles, your car is most likely due for new ones. And you may experience misfires until you replace them.
Mass Airflow Sensor
This component measures the amount of air entering the engine to ensure the right fuel-to-air ratio gets burned. If this sensor is on its last leg, the ratio will be altered, and the check engine light will come on.
Oxygen (O2) Sensor
The oxygen sensor, or O2 sensor, works similarly, but it is in the exhaust. It measures the unburned oxygen present in your emissions. If there is too little or too much unburned oxygen. It will send a warning to your vehicle’s onboard computer.
Catalytic Converter
The catalytic converter is the last place you want your check engine light to be about. Your vehicle cannot run without this exhaust piece, and it is pricey to replace. If the cat can’t properly transform your exhaust, it can emit a rotten egg smell along with harmful gasses.
The check engine light is set off by the vehicle’s onboard computer system and a trained technician can use this to determine what additional diagnosis is necessary. If you notice this light on your dash, take your car in to a reputable shop, like Airpark Auto Pros to get it checked. Be cautious about getting a code scan (check engine light scan) at a parts store. The codes by themselves don't tell the whole story and you can spend a lot of money on parts and not even fix the problem. Whether its Airpark Auto Pros or another high quality shop, you'll want a trained, experience and certified technician to help you with this one.