Check Engine Lights: Common Triggers

What’s Causing Your Warning Light

How It Works

Most drivers are familiar with the check engine light. It’s that yellow dashboard indicator that makes you worry about what’s wrong with your vehicle. As part of the vehicle’s computers that monitor performance, it activates when something isn’t quite right under the hood. But to the driver, it’s just a yellow light! The only way to tell exactly what is causing your vehicle’s check engine light is to visit a professional. Using a code-reader, they can quickly diagnose the issue.

While diagnostics are the best way to decipher the cause, it can still be helpful to have an idea of what to expect. At Jeff’s Auto Repair, we frequently see the same triggers. To help drivers get a better idea of what the check engine light means, we’re sharing them with you!

Common Triggers

1. Loose Gas Cap

Something as simple as not tightening your gas cap could trigger the check engine light. If you’ve just stopped at the gas station and notice the light is illuminated when you drive off, it might be a good idea to double check that you’ve secured the gas cap in place. If it’s not, fuel vapors leak and impact the whole fuel system, reducing gas mileage and increasing emissions. Replace a lost or cracked gas cap to prevent the escape of fuel vapors.

2. Oxygen Sensors

Oxygen sensors monitor the amount of unburned oxygen that escapes through the exhaust to measure how much fuel is burned. In other words, they use the information to track the fuel economy. A faulty oxygen sensor fails to alert when gas mileage drops or when emissions increase. When the sensor gets dirty, it may need a simple replacement. Avoiding this could lead to much more costly repairs, like a failed catalytic converter.

3. Failed Catalytic Converter

A vehicle’s catalytic converter converts carbon monoxide and other harmful exhaust gases into harmless compounds. If it fails, your vehicle’s gas mileage will suffer. You might also notice decreased power when you press the gas pedal. Ignoring a failed catalytic converter won’t solve anything — in fact, your car will eventually stop moving completely.

Get Repairs

Once you notice your vehicle’s check engine light, your first course of action should be to check the gas cap. After that, head to Jeff’s Auto Repair in Seattle, Washington for diagnostics and repair!