What Does it Mean When My Check Engine Light Comes on?

Nothing strikes fear in a driver quite like seeing that check engine light suddenly showing up on the dashboard. The check engine light can come on for many reasons. And even though it can cause a little panic, most of the time, the check engine light is not a sign of anything serious

However, that doesn’t mean you should ignore it. The light doesn’t just turn off by itself. So, your best move is to bring your vehicle into our Downey auto repair shop to find out why it came on.


Determine the Problem

The check engine light can turn on for several reasons. We’ll use our advance diagnostic tools to pinpoint the exact problem. Just remember, although it’s possible your vehicle has a serious problem, most likely it’s something simple. So don’t panic. These are the usual reasons your check engine light comes on.


1. Oxygen sensor – your oxygen sensor tracks the unburned oxygen from your vehicle’s exhaust. When the sensor goes bad, your computer can’t get the right info. This is one of the most common causes of the check engine light turning on. Most vehicles typically have two to four sensors. Our diagnostic tool can determine which sensor has gone bad.

2. Gas Cap – it might not seem possible, but if your gas cap is busted or loose, it can cause an error code in your fuel system, because it allows fuel vapors to escape. If your cap isn’t broken and tightening it doesn’t clear the check engine light, then please bring it into our Downey CA auto repair shop to find the problem.

3. Mass Airflow Sensor – the mass airflow sensor ensures the computer sends the right amount of fuel based on the amount of air passing through the engine. If this sensor goes bad, fuel economy can suffer, and your vehicle might stall. It’s a good idea to replace this part annually for the best engine performance. If you’re not comfortable changing it yourself, just bring it in to Glenn’s Auto Service.

4. Catalytic Convertor – your vehicle’s catalytic converter reduces gases from your exhaust. If it goes bad, your gas mileage will suffer, and your car won’t accelerate properly. Eventually your vehicle won’t even run. So, if your catalytic converter is bad, please come see us right away.

5. Spark Plugs and Wires – although they’re small, spark plugs and wires play a key part in your engine’s performance. If your wires are worn out or your plugs are old, then your vehicle might jolt when you accelerate. Spark plugs wear out over time, and you can’t repair them. They must be replaced. The good news it it’s a simple and affordable repair that doesn’t keep your vehicle out of service for long.


Proper Diagnosis from Glenn’s Auto Service

So, which problem does your vehicle have? Most cars come with computers, which makes diagnosing any issue much easier. As mentioned earlier, with our advanced diagnostic tools, we quickly determine what’s wrong with your car, truck, crossover, or SUV. We’ll get the code from our scanner and interpret what it means. With that information, we’ll know what’s wrong and what we need to fix it.

So, bring your vehicle into Glenn’s Auto Service if your check engine light comes on, and leave the guesswork out. We’ll get you back on the road quickly and safely. Just call us at 562-359-4232 or click here to set up an appointment online for all of your auto repair needs.


We are your trusted Downey, CA auto repair shop for all services and repairs on all makes and models, including:

Subaru auto repair in Downey, CA

Chevy auto service and repair in in Downey, CA

Subaru auto repair in Downey, CA

Honda auto service in Downey, CA

Scion auto repair in Downey, CA

Nissan auto service in Downey, CA

Ford auto repair in Downey, CA

Chrysler auto service and repair in Downey, CA


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