Common Causes Of An Illuminated Check Engine Light: What To Do
Picture this scene: It’s the end of a great weekend getaway. You’ve spent a couple days relaxing and de-stressing and there are still a few precious hours left before you have to start worrying about anything. That’s before the “check engine” light on your dashboard blinks to life. Is there any faster way to ruin your day?
The check engine light, for all its mystery and ominousness, is a pretty straightforward part of your car’s on-board diagnostic system. While you can rest assured that an illuminated light does mean you have trouble, not every cause that can illuminate the light is serious.
Presented here are the five most common causes of engine light activation. While you might need to start looking for professional auto repair in Houston TX after that light comes on, you might also be facing something simple that you can actually fix yourself.
1. Faulty Sensor
Your car uses a suite of oxygen sensors (generally two to four of them) to monitor the interaction of oil and air in your engine. If one of these sensors fails, inaccurate data may lead to emissions problems and a cost reduction in engine efficiency.
Oxygen sensors typically fail when they become obstructed by oil ash. This ash disturbs the sensor’s ability to accurately sample the oil-oxygen mix and determine when a change is needed. The good news is that changing an oxygen sensor is actually well within your abilities as long as you learn where to find it. (Your owner’s manual will provide invaluable guidance here.) If you leave a sensor replacement up to a professional mechanic, it will generally cost you roughly $200. Getting the sensor fixed quickly should be a top priority.
2. Faulty Gas Cap
This seems like a far too trivial problem to turn on your dreaded check engine light. The truth of the matter is that a leaky gas cap can upset your car’s entire fuel ecology. Leaking gas vapor can lead to a significant reduction in fuel efficiency. Check and confirm that your fuel cap is tightly sealed. Look for cracks in the cap as well. If you need a replacement, you can find (and install) a perfectly serviceable one for just $3.
3. Spark Plug / Wire Issues
A faulty spark plug is more likely to start misfiring and causing jerky acceleration while your car is in motion. Modern spark plugs are generally very durable – usually lasting up to 100,000 miles – but a manufacturing defect may cause one to fail early. If you encounter this problem yourself, you need to replace your flawed spark plug as soon as possible. Spark plugs are easy to replace on your own, and they’re generally immediately accessible as soon as you open the hood. Take the time to let your car cool down before removing them! Though a plug spanner may allow you to safely remove a hot spark plug, it still has the potential to burn your fingers.
4. Mass Air Flow Sensor
If your car’s mass airflow sensor fails, you’ll have issues with lower mileage, higher emissions, and inopportune stalling. The air flow sensor has either worn out or been installed improperly if this is the case. A replacement sensor will generally cost $200 to $300 depending on your car’s make and model.
5. Catalytic Converter
Catalytic converters play a vital role in reducing your car’s exhaust. If the code attached to your engine light indicates a problem with the catalytic converter, you’ll probably be able to tell that acceleration has fallen off and your mileage is getting worse. A replacement catalytic converter may cost as much as $2,000. This is a job best left to experts, so leave it up to an experienced mechanic unless you’re a professional yourself.
While these five issues account for most engine check lights, there are many other possibilities. There might even be perfectly explainable and harmless factors that cause your light to come on. Something as simple as errant moisture on a high-humidity day might cause the light to illuminate.