What is a check fuel cap light is on inspection?

During a check fuel cap light is on inspection, a mechanic will check for any underlying reasons for the sudden appearance of the “check fuel cap” warning, such as a dirty O ring.
Your dashboard’s “check fuel cap” light warns you if the car’s fuel cap isn’t safely or properly secured to the car. It’s simply telling you to check the fuel cap to make sure it’s fastened correctly and securely. But if there is a more serious underlying issue, you will need to take your car to the repair shop.

How your mechanic will perform a check fuel cap light is on inspection

If you tried tightening the fuel cap and the light is still on, your mechanic will need to perform a more thorough inspection, which involves the following:
  • Check that the fuel cap is secured properly, even though you already checked this yourself. It could be as simple an issue as catching the grooves weird or just a lack of familiarity with the car.
  • Check the fuel cap O ring to make sure it isn’t dirty or damaged. The mechanic may need to simply clean the O ring, or clean and lubricate it, so it makes a full connection.
  • Check the fuel cap seals to make sure the cap is able to close properly.
  • Check for a problem with the fuel cap indicator to make sure the sensor isn’t malfunctioning.
  • Check the fuel filler neck to make sure it isn’t dirty or damaged, as this can trigger a check fuel cap warning light as well.
  • Check the catalytic converter, the most expensive potential problem. Some problems with the catalytic converter might trigger the check fuel cap light. These problems are incredibly rare, but it does sometimes happen.

Do I need a check fuel cap light is on inspection?

Here’s how to tell if your fuel cap is in need of a check fuel cap light is on inspection:
  • The “check fuel cap” light is on.
  • The “check engine” light is on, which could indicate any number of problems. But if your car doesn’t have a “check fuel cap” light on the dashboard, it might show as a “check engine” light instead.
  • You’ve left the gas station but you still smell gasoline. Pull over as soon as you’re able and check the fuel cap.

How important is a check fuel cap light is on inspection?

It might seem like a small, simple problem, but it’s one you need to take seriously and fix immediately. A loose fuel cap or worse—driving without the fuel cap—can have dire consequences for you and your car, especially if your fuel tank is full enough for spillage.
If you’ve tightened the fuel cap and the “check fuel cap” light is still on, getting in to see a mechanic should be considered urgent. You don’t want to drive around long term with a faulty fuel cap or with a potential fuel leak.