The 9 Most Common Causes for the Check Engine Light

As you may or may not already know, your vehicle's "check engine" light is essentially a catch-all warning light. It can be tripped by a number of different sensors and systems within your car. Today's modern vehicles with more advanced computer systems may be able to give you a more specific notification along with the check engine light coming on, but older vehicles will not be quite as helpful.

Here are 9 of the most common causes for the check engine light being illuminated in your car:

1. Loose Fuel Cap

This one is actually very common. Sometimes you don't quite screw the gas cap on all the way (listen for that click) or maybe you forgot to replace it altogether. Either way, it's an easy problem to look for and fix.

2. Oxygen Sensor

Your emissions system will have oxygen sensors that are there to detect exhaust issues. If there is an emissions problem, it will likely trip the check engine light. Sometimes, the sensor itself can fail or give faulty readings and may need to be replaced.

3. Other Emissions Problems

The emissions/exhaust system is the most likely culprit for many check engine lights being illuminated. There could be an exhaust leak or a problem with the catalytic converter. The mass airflow sensor (MAF) is another sensor that is easily tripped or can fail. It's usually a good idea to get your exhaust system inspected if your check engine light is on.

4. Spark Plugs or Ignition Coils

Another very common reason the check engine light comes on is when there is an issue with one of your spark plugs or ignition coils. Things may not be firing correctly, which can cause engine performance loss and the check engine light is letting you know that there is a problem.

5. Wiring Issues

From the battery to the spark plug wires and the ignition system in between, there is a lot of wiring that is vital to your vehicle firing up and staying running right. Any loose connection or damaged wire can cause trouble and may illuminate the check engine light.

6. Transmission

Your transmission may have its own specific warning lights, but transmission damage can also cause the check engine light to come on and let you know there is a problem. You may just be overdue for a transmission service to replace the fluid, or there could be more significant internal damage to address.

7. Cooling System

Again, an overheating car will have its own temperature warning lights and gauges. However, the check engine light may also be illuminated when there is a cooling system problem. 

8. Fuel System

If your engine isn't getting the proper amount of fuel or the fuel itself is contaminated because the filter needs to be replaced, the check engine light may come on to let you know the fuel system is affecting the vehicle's engine performance.

9. Engine Oil

You may be low on oil or the oil itself may be old and contaminated. This will lead to engine problems and loss of performance that may trip the check engine light. You might just be overdue for an oil change or there may be a leak somewhere in the fluid system. 

These are just a few of the most common causes for the check engine light coming on. If your check engine light is on (especially if it is red or flashing, which indicates a major problem that requires immediate attention), get your vehicle looked at by a professional mechanic. They can run diagnostic tests and inspect the parts to determine the exact source of the warning light.

If you are having engine issues or other car troubles in Northern Delaware, contact Fox Run Auto today at (302) 597-9205 or schedule your service appointment online.



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