Why is My Check Engine Light On?
If your check engine light is on, you’re not alone. Here at Fisher Service in Boulder, we get quite a few Denver area drivers who bring their car into us with that very same problem. And that means there are probably even more of you out there who aren’t bringing your car in when the check engine light is on. It can be frustrating to have such a vague problem—when your fuel light comes on, you know exactly what’s wrong—but engines are complicated machines and require a technician to inspect the problem.
The causes for your check engine light turning on are numerous—some systems have over 1,000 different diagnostics that they check periodically—and you can’t just assume that your engine is fine because your car is still drivable.
Most Common Reasons For a Check Engine Light to Go On
While there can be hundreds, even thousands of different causes for your check engine light to turn on or start flashing, we’ve found that there are typically five major culprits, many of which you’ll want to trust a certified technician at Fisher Service to fix for you.
- Oxygen Sensor: The oxygen or O2 sensor checks how much unburned oxygen comes out in your exhaust and monitors how much fuel is being burned. Over time it can develop faults or get covered in oil ash and send false signals to your engine, reducing fuel efficiency and increasing your emissions. Not replacing your oxygen sensor can lead to a busted catalytic converter, one of a car’s most expensive replacement parts.
- Loose or Faulty Gas Cap: Your check engine light comes on for this to keep the fuel vapors from leaking out of your tank and throwing off your entire fuel system. If your gas cap is loose, that’s an easy fix you can handle on your own. However, if it’s faulty, you may just need to order a new one. There’s also a chance the seal could have problems with it, in which case you’ll need to have a pro inspect the problem.
- Catalytic Converter: If you don’t get that O2 sensor checked, you’re going to run into catalytic converter problems. Your converter helps to reduce emissions, and if it’s failing, you may notice a richer exhaust vapor smell as well as a decrease in fuel efficiency. If your catalytic converter fails, you won’t be able to keep your car running for long.
- Mass Airflow Sensor: The mass airflow sensor lets your engine know how much air is coming in and how much fuel to use. When it goes bad, it can increase your emissions, decrease your efficiency, and cause your car to stall. Usually this can be solved by replacing your air filter, but in the event that you’ve got a bigger problem, we recommend drivers let our technicians take a look just to be safe.
- Spark Plugs and/or Wires: Of these five causes, this is likely the one you’re most familiar with. Most drivers know that they need to change their spark plugs and wires periodically. Your engine will let you know if spark plugs are bad or going bad, but if you don’t act quickly, you could end up with one or more cylinders failing to fire, which can cause significant long-term damage. We’re happy to replace your plugs and wires, and the new set will last you a long time.
Run Engine Diagnostics to Pinpoint Your Check Engine Light Cause
Professional technicians like ours are able to figure out why your check engine light is on because we have professional diagnostic equipment. We hook up your car to our computer, and your car tells it what’s wrong. Of course, this doesn’t always pinpoint the cause, so we have the latest in diagnostic software and hardware to figure out just why your check engine light came on and what we can do about it.
Here’s a quick look at what our normal diagnostic procedure looks like:
- Retrieve Data: We pull the codes directly from your car’s computer as well as any data from critical sensors (like your oxygen sensor) to give us an idea of what could be wrong and where we should look.
- Verification Testing: Next, we verify that the information we’ve received from your car is correct, testing to see if your vehicle meets proper specifications including fuel, ignition, and emissions systems.
- Pinpoint Testing: We perform electrical and mechanical tests as well as visual inspections of your vehicle’s systems to narrow any potential issues further so that we know just what to fix.
- Research Technical Service Bulletins: We do our research to see if there is a pattern of failure with a certain type of vehicle before diving into repairs, as it can let us know what has worked for similar issues on similar vehicles.
- Repair Your Car: By now, we should have found what is wrong with your vehicle and given you an estimate on expenses and repair time. This is when our techs bring your vehicle back into working order.
- Verify Repair: We don’t just send you out into the wild assuming our repair worked—we double check our repair job and retest to make sure it fixed the problem.
Find Out Why Your Check Engine Light is On at Fisher Service!
No matter the cause, if your check engine light is burning bright, flashing, or just turning on occasionally, it’s not something to take lightly. Fisher Service is conveniently located in Boulder, and we have drivers all over the Denver area that are more than satisfied with our maintenance and repair services. If your check engine light is on, you can count on us to figure out what the problem is.