Why is My Check Engine Light On?

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Back in the old days before cars had the benefit of computer technology under the hood, we didn’t have such things as Check Engine lights to let us know that something needed attention. Usually, an unaware motorist would simply find themselves stranded by the side of the road, all the worse for the wear and unable to call for help with the invention of cell phones still decades away. Nowadays, we’ve got it good. Red and yellow light indicators on our dashboards pop on to let us know when it’s time to lift the hood and take a look – or get ourselves to the nearest auto mechanic in a hurry to let them have a gander. But what exactly does the Check Engine light on mean?
How is Your Check Engine Light Behaving?
First things first. Your Check Engine light can mean quite a number of things, but depending on how it behaves, you can get an idea of the severity of the issue. A flashing Check Engine light is indication of a much more serious issue than a permanently illuminated one. Here are a couple of hard and fast rules to remember.

  • If your Check Engine light is flashing, this means that the issue is urgent and that you may be minutes away from an all-out breakdown or serious damage to your vehicle’s systems. When this happens, it’s imperative that you pull over right away. In worst case scenarios, continuing to drive your vehicle could end up causing some incredibly expensive damage.
  • If your Check Engine light is glowing red but not flashing, the issue is usually not as urgent. But this isn’t a pass to simply ignore it until you find the time to get around to checking out the issue. Even minor issues, if gone unattended, can cause serious damage to your car. As soon as you get a chance, make an appointment to visit an auto mechanic to diagnose the problem.

So What Exactly Does that Check Engine Light Mean?
Unfortunately, there’s no way of knowing exactly what the problem is simply by looking at the light. Unlike your Oil indicator or gas gauge, the Check Engine light could illuminate for a wide variety of reasons. Here are just a few of the possibilities.

  • Engine misfire or problems with your catalytic converter.
  • A loose gas cap. This is simply remedied by tightening your gas cap, but this doesn’t mean your Check Engine light will turn off automatically. In fact, it may take several days to turn off. If the light is still on after a few days, have a mechanic take a closer look. They may simply need to reset the indicator if they find no other problems.
  • Bad or aging spark plug wires.
  • Failure in your vehicle’s emission control system.

Always bear in mind that the longer you continue to drive your vehicle after a problem has come to your attention, the higher the bill may end up being when you finally do get it looked at by a professional. For this reason, always pay attention to the warning lights that come on as you’re driving. They’re not just there for decoration – they’re there to ensure you’re aware of issues before they develop into serious problems.