The Check Engine Light: What It Means and What to Do

February 12th, 2021 by

A gauge cluster in a vehicle is shown from an angle.

It can happen out of nowhere and disrupt your day. If you drive a Nissan, this issue can land you at a Chicagoland Nissan service center before you know it. There you are, taking a seat in the captain’s chair. You turn the ignition, hear the familiar bells and whistles as your car welcomes you in. Lights and symbols flash on your dashboard, but then, it happens: one of the lights activates but never goes away.

It’s that dreaded “check engine” light. This yellow-orange engine shape on your dash can throw even the most trained auto expert for a loop, particularly because it’s so non-specific. Something is wrong, and it’s difficult to ascertain what. Your car knows what’s wrong, but it’s not exactly relaying the message in a way that’s helpful.

So why would your check engine light even activate? What is your car trying to tell you? Unfortunately, there are several different reasons why your car may display this symbol on your dash, each of which is extremely specific, ranges from routine to severe, and may require wildly different repair/maintenance services. Overall, “check engine” is as vague as it sounds: your car wants you to drive it to a trustworthy auto center, where a diagnostic team can read your vehicle’s computer and determine exactly what the problem is. That may not be your preferred way of communicating with your car, but that’s the system engineered into existence, so your only resort as a car driver is to answer the call.

Common Check Engine Lights

The chack engine light in a vehicle is lit.

Some auto experts may claim to know the truth behind check engine lights, but this alert can symbolize so many different problems that there’s no hope in narrowing it down on your own. That is, unless you see other signs of common automotive issues. These are some of the most common issues that can trigger the check engine light, or CEL.

The first is an issue with the engine’s oxygen sensors. Your car is designed to detect a safe range of oxygen levels in your engine exhaust system. If the oxygen levels are out of range, this can mean that the vehicle is burning more fuel than it needs to, your fuel economy is compromised, there’s an issue with the fuel injector, or there’s a leak somewhere in the engine. Note that even in the range of CEL codes that represent oxygen sensor issues, there are still many different, specific problems at play, including failed sensors, improper catalytic converter operation, and more.

Gas cap problems can also signal the check engine light, the most obvious being a loose fit. Many people have a casual view of their gas cap when they fuel up – isn’t it funny when you drive away, and it’s still hanging off? – but this part is actually a significant piece of what’s designed to be an airtight fuel system. Your engine is notifying you that a loose gas cap has allowed outside air into the fuel system, which can interfere with its performance. If your CEL is on, a quick look at the gas cap may be the only problem, and, luckily, just tightening it up may be enough to dismiss the annoying notification.

Another common CEL trigger is spark plug failure. The spark plug isn’t an electric plug that goes into an outlet – as many people may assume – but rather is a stopper of sorts that “plugs” the combustion chamber in your engine, forming a tight seal. More importantly, it conducts a spark that ignites the fuel in the engine, which then generates power. Sadly, spark plugs and their wires fail from time to time, and your check engine light may be the sign that this is exactly what happened. If you don’t replace failed plugs, they can misfire and interrupt vehicle operation, potentially causing engine damage.

Sadly, this is just the beginning of what the check engine light can signify. Who knows why cars are designed in this way, but you’ll just have to think of the dreaded CEL as a “report to maintenance” symbol. And yet, many drivers may fail to take this symbol seriously, as if it’s so vague that you might as well shrug it off. Here’s why you shouldn’t do so.

Ignoring the Signs

Your car may be able to operate on a base level when the check engine light is on, but not for long. Depending on what exactly your car is trying to tell you, parts like the catalytic converter or spark plug may be failing completely, and your car won’t run adequately for long. Other issues signified by the CEL may decrease your vehicle’s performance, fuel economy, or safety. Ultimately, ignoring the light means putting your vehicle at risk.

What if you’re on a tight budget and don’t want to spend money on auto services? Sadly, ignoring a check engine light can actually be worse for your finances than taking your car into an automotive service center for a quick solution. Your car’s health is, in many ways, much like your body’s: take care of it now, and it’ll be healthier in the long run; ignore health problems, and they can get much worse, quickly. Your vehicle can even fail and leave you stranded.

A blue vehicle is on a tow truck headed for a Chicagoland Nissan service.

Answering the Call

A check engine light can refer to not just multiple problems but multiple families of engine problems, so how do you identify the root of it all? It’s easy; just visit your local automotive service center. Automotive experts have advanced diagnostic equipment that they can use to read your vehicle’s computer and get a precise diagnostic code. This code, which is stored in your engine, will identify what’s wrong or, at the very least, point an automotive team in a general direction. A diagnostic reading, coupled with a mechanic’s inspection, can soon determine the root cause of engine troubles.

So there you have it; as aggravating as it may be, as intrusive to your daily plans as it can feel, the best course of action is to take your car to a service center. There’s one exception to this rule, and that’s when the CEL is blinking rather than remaining steady. A blinking check engine light is trying to catch your attention urgently, and it means business. Pullover and call your local Chicagoland service center or favorite roadside assistance service. Your car is telling you that it’s no longer safe to operate, and someone will need to assist you right away.

Going to the Pros

If you’re wondering who to go to for check engine light services here in Chicagoland, look no further than Thomas Nissan of Joliet. Our dedicated service team has the knowledge, equipment, and parts necessary to address whatever may be triggering your check engine light quickly and easily. While we may specialize in Nissan vehicles, our talented automotive service team can tackle a wide range of problems on all vehicle makes, models, and years.

The minute you see your CEL signal, it’s time to act. Visit our website or give us a call to schedule service, ask an expert a question with our easy online message service, and learn about our wide range of service amenities. Or, just stop by and visit our automotive service center in person. For urgent cases, we offer towing services, and we even have loaner cars should you need to leave your vehicle in our trusted hands. At Thomas Nissan of Joliet’s service department, our #1 goal is to get your vehicle back to you in great condition as quickly as possible and at a low cost to you.