5 Most Common Reasons Why Your Engine Light Is On

As the service advisor at Presley’s Service Centre, part of Presley’s Auto Showcase, I have seen many check engine lights. Your vehicles check engine light is designed to turn on when certain sensors are malfunctioning, it can be difficult to figure out what the Check Engine light is trying to tell you to, but there are a few things you can check yourself.

When your check engine light suddenly makes an appearance on your dashboard, make sure to check the following five areas of the car, before bringing it to Presleys Service Centre:

Reason #1: Faulty Spark Plugs

Spark plugs serve the purpose of igniting the fuel/air mixture into the engine. They are some of the simplest components to replace when faulty, but they’re also prone to burn out, crack or worn.

If your spark plug cables and wires are even slightly worn out, or you havent changed them is the last year or so they will misfire and cause the Check Engine light to turn on. Take a close look at the spark plugs and wires for any signs of damage.

Reason #2: The Gas Cap is Loose

Many vehicles have sensors around the gas tank that go off when there is too much or too little pressure in the tank. If you haven’t tightened the gas cap properly or many times cross thread the cap this can allow air or moisture into the system which sets off the sensor. Turn off the car, retighten the gas cap, wait a few seconds and start the car again; there’s a good chance the Check Engine light will disappear promptly or after a short period of time.

Reason #3: The Fuel Injector is Clogged

The fuel injectors can become clogged with dirt and oil, which means the gas isn’t getting to the engine properly. The fuel injectors must be clean or they won’t be able to inject the proper amount of gas into the engine. If this is the case, you’ll notice that it takes longer for the car to increase speed when you push down on the accelerator.

You can try a fuel injector cleaner or flushing the system both available here at Presley’s Service Centre and it may just turn off your Check Engine light.

Reason #4: The O2 Sensor is Faulty

The oxygen sensor is responsible for measuring the amount of oxygen in the exhaust; it will send out a signal to your engine’s computer to either add or reduce the amount of fuel being delivered to the combustion engine when you push down on the accelerator. If it’s faulty, you will probably be getting really bad gas mileage, or you’ll notice it’s hard for the car to pick up speed. A faulty sensor will also make the Check Engine light turn on.

Reason #5: The Exhaust Gas Recirculation Valve is Dirty

The exhaust gas recirculation valve (EGR) is designed to reduce exhaust emissions by recirculating exhaust gases into the engine’s intake stream. If this valve gets clogged with oil or dirt, or it starts to deteriorate, you might notice a strong smell of gas every time your start the car; this will also set off the Check Engine light.

If none of these causes are the culprit. You can book an appointment at Presley’s Service Centre for an oil change and a free engine analysis.