Blog Car Care Advice Top 8 Causes of a Buick Check Engine Light & What to Do
Car Care Advice

Top 8 Causes of a Buick Check Engine Light & What to Do

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The Check Engine Light on the dashboard of your Buick Encore could range from something inconsequential like a loose gas cap to serious issues that need immediate attention, like failing engine sensors.

While this warning light can be worrying, it’s manageable once you know what to do

So, what does the Buick Check Engine Light mean?
How do you reset the check engine dashboard light?

We’ll walk you through everything you need to know about the Buick Engine Light.

This Article Contains

Let’s get started.

What Causes the Buick Check Engine Light to Illuminate?

Here are eight reasons why the Check Engine warning light can come on in your Buick:

1. Loose Gas Cap

The gas cap maintains the pressure inside the fuel tank by preventing gas fumes from escaping as you drive. It also prevents dirt, dust, and other contaminants from entering the fuel tank. If the gas cap is old, cracked, or missing, your fuel efficiency will drop and trigger the Check Engine Light, even on new vehicles.

2. Failing Catalytic Converter

A faulty or clogged catalytic converter is also why your engine light is on. The catalytic converter is an essential component in the emissions and exhaust system. It converts harmful emissions and unburned fuel into safer gaseous molecules before releasing them into the atmosphere.

Driving with a clogged catalytic converter can severely impact your fuel economy, decrease engine performance, and overheat the engine.

3. Worn Spark Plugs or Spark Plug Wires

The spark plugs create a high-voltage spark that ignites the air-fuel mixture in the cylinder, allowing your engine to start. Meanwhile, the plug wires carry current from the ignition coil to the spark plugs. 

Driving with worn spark plugs and frayed spark plug wires can cause a misfiring engine, reduced fuel efficiency, and bad engine performance. Faulty plugs, plug wires, or ignition coil can even prevent your vehicle from running altogether, thus triggering the engine light.

4. Faulty Oxygen Sensor

The oxygen sensor or O2 sensor in your Buick helps the Engine Control Unit (ECU) regulate the engine’s air-fuel ratio. A faulty O2 sensor causes the ECU to supply the engine with the wrong amount of fuel. An engine running on the wrong air-fuel mixture can damage the catalytic converter and spark plugs. Both of these can activate the CEL. 

Your car will also generate excessive smoke and odor and risks total engine failure, which is a far more expensive repair job. 

5. Faulty Mass Air Flow Sensor

The mass airflow sensor measures the amount of air entering the engine during combustion and helps regulate the proper air-fuel mixture. If the mass airflow sensor fails, it causes your engine to run lean, leading to a misfiring engine, an active engine light, poor fuel economy, and potentially more damage requiring a costly repair.

6. Vacuum leak

Another cause for an illuminated engine light is a vacuum leak. The vacuum system lowers the amount of harmful emissions the engine releases by returning fumes and unburned fuel vapors back to the engine for combustion.

If the engine is experiencing a vacuum leak, you’ll notice higher RPMs when idling and a glowing Check Engine Light.

7. Weak Battery

A weak car battery can also trigger the Check Engine dashboard light. Without the battery, your car won’t start, the headlights won’t come on, and your center console can’t function.Issues with the battery can also set off the battery light on your dashboard.

8. Improper Installation of Aftermarket Items

Aftermarket parts can put extra load on your engine and the car battery, triggering the Engine Light of your Buick Encore — especially if installed poorly. While getting Original Equipment Manufacturer (OEM) accessories is costly, it could save you from the costly repair down the line.

So, how should you address the Buick Check Engine warning light?

What to Do if Your Buick Check Engine Light Turns On?

The Buick Engine Light can come on in three different forms. Here’s what you should do for each case:

A. Illuminates Under Certain Circumstances

When the Check Engine Light comes on irregularly, you should keep an eye on the engine’s performance. This typically means an engine component is on the verge of complete failure. You can still drive your vehicle, but it’s best to head to a Buick service center immediately.

B. Steady Check Engine Light

A steady engine light on your Buick’s dashboard means something’s wrong with your engine and must be fixed. In some cases, the engine might automatically enter “limp mode,” where the engine power reduces. Sometimes, it can also mean that your vehicle is due for maintenance, like an oil change.

Though the vehicle may operate normally, it’s best to bring your car in for service ASAP to prevent further issues. 

C. Flashing Check Engine Light

If you encounter a red or flashing check engine light that stays as you drive, you should immediately pull over and turn the engine off.

A red flashing engine light means a critical engine problem needs immediate attention. Driving in this state would put your car at risk of a complete engine failure – an even more expensive repair. No matter the situation, when the Check Engine Light flashes, it’s highly advisable to immediately get your car towed to the nearest Buick service center or a certified mechanic. 

Now, let’s see how the Buick Check Engine Light resets.

Will the Check Engine Light Reset Itself?

The Check Engine Light will automatically reset after fixing the underlying problem. Sometimes, it’ll take between 20-40 miles worth of driving to go off.

However, if you’ve already driven long enough and the light stays on, that would mean that another problem has occurred, and you should get your car back to the mechanic ASAP. 

To fix this, a certified mechanic would use an OBD II scanner tool to look out for any new check engine light codes and fix them. Finally, they’ll erase the check engine light codes from the system, which automatically turns off the engine light.

But, if the light stays on, they’ll manually turn it off by disconnecting the battery. Here’s how:

Your Buick’s engine light diagnosis and repair come at a cost. Let’s take a look.

How Much Does a Buick Engine Light Diagnosis Cost?

A Buick Check Engine Light diagnosis and repair can cost between $88 to $111

The huge gap exists because the Buick engine light doesn’t indicate the exact engine problem. So, the mechanic would need to conduct several tests or replace different parts with varying prices to get it fixed.

Final Thoughts

Whether you’re driving a  Buick Encore or Enclave, the Check Engine Light could indicate a faulty oxygen sensor, a fouled spark plug, or a fault in the exhaust system.

If you see the Check Engine Light on your dashboard, it’s best to get it checked out immediately by a professional like AutoNation Mobile Service. AutoNation Mobile Service is a mobile auto repair service that offers easy scheduling, upfront pricing, and a 12,000-mile or 12-month warranty to ensure your peace of mind.

Contact us today for a Check Engine Light diagnosis, and our technicians will fix your Buick right in your driveway.