What Does the Check Fuel Fill Inlet Warning Light Mean?

The check fuel fill You can often trace the inlet warning light back to a loose gas cap or a leak in the EVAP system. Learn more here.
Written by Melanie Krieps Mergen
Reviewed by Melanie Reiff
background
Many issues that cause the check fuel inlet warning light to illuminate result from a loose or damaged gas cap or a leak in the EVAP system. In some cases, the solution could be as simple as tightening the gas cap, while in others, you may need a mechanic to repair it.
Having the “check fuel fill inlet” warning light appear on your car’s dashboard can be a confusing experience—especially if it’s never happened to you before. 
Luckily, finding the fix doesn’t have to be that complicated. Here to break down the common causes of fuel inlet problems, how you can respond, and when it’s time to see a mechanic is
Jerry
, the
trusted super app
that helps drivers save time and money on
car insurance
shopping.
Compare insurance quotes from 50+ insurance companies with Jerry in under 45 seconds
Compare insurance quotes from 50+ insurance companies with Jerry in under 45 seconds
icon4.7/5 rating on the App Store | Trusted by 5+ million customers and 7 million cars
icon4.7/5 app rating | Trusted by 5M+ drivers

What is a fuel fill inlet?

Whether or not you know it by name, the fuel tank fill inlet is arguably one of the components of your vehicle that you interact with the most.
A fuel inlet is simply the opening where you pour fuel into your vehicle’s gas tank. 
The fuel inlet refers to the gas cap and the inlet pipe you place the fuel pump nozzle into, leading to the fuel tank.

What does a check fuel fill inlet warning light mean, and what causes it?

While any vehicle can have fuel inlet issues, some may display the problem under a different message, like the check engine light. The more specific “check fuel fill inlet” message is a particularly common feature in Ford vehicles, like the
Ford Fusion
or the
Ford F-150
.
When the check fuel fill inlet warning message appears, it usually means your vehicle has detected an issue with one of the following: 
  • The gas cap
  • A leak somewhere in the evaporative emissions control system (EVAP system)
  • A blockage from debris in the fuel inlet
Of course, different vehicles can have various fuel inlet features. For that reason, if your fuel fill inlet comes on, you should check your owner’s manual for guidance for the likely causes and actions you should take in response.
Here’s a closer look at some of the most common triggers for the check fuel fill inlet warning light.

Loose fuel cap

A loose gas cap is the most straightforward fix that could cause the check fuel fill inlet warning light in your vehicle to turn on. 
The fuel cap is a vital part of the EVAP system because it prevents dirt or other contaminants from entering your fuel tank—and harmful gas pollutants from escaping it. It also creates a vacuum pressure seal necessary for the vehicle’s fuel to flow through the system.
If you forgot to replace your fuel cap or close your fuel door at the gas station, simply putting it back in place should cause the light to turn off.
If your fuel cap is missing rather than loose, however, it’s important to replace it as soon as possible to prevent contaminants from entering your vehicle and causing damage to the fuel system or other components.

Fuel cap over-tightened

While a tight seal on your gas cap is important, be careful not to over-tighten it. This could cause problems with the pressure level in the fuel tank. It could also damage the fuel inlet’s seal or the cap itself, triggering the check fuel inlet warning light.

Fuel door problems

Some vehicles have capless fuel inlets, like specific model years of the Ford Flex or Ford Explorer. A loose or open fuel door can cause the warning light to activate on these model cars.

Dirt and debris in fuel tank

Without a proper seal, dirt and other debris can enter your fuel tank and contaminate your fuel, which can end up damaging other parts of your vehicle if they start making their way through your fuel system. 
If enough contaminants build up, they could cause blockages in your fuel system and cause the check fuel fill inlet light to come on.

Faulty sensor

The fuel tank pressure sensor (FTP) is what monitors conditions that could indicate EVAP system leaks and turns on the warning light on your dashboard. If there’s a problem with the sensor itself, it could also turn on the check fuel inlet light. 

Determining issues with the gas cap

One of the major reasons that a check fuel inlet light illuminates is due to problems related to the vehicle’s gas cap. The following are some of the ways a loose, worn out, or damaged gas cap can cause the fuel inlet warning light to turn on and the signs that can accompany them.

Fuel cap damage

If there’s a problem with your fuel filler cap that won’t allow it to tighten properly, it might need replacing. You can generally find compatible replacement fuel caps at auto parts stores.
If you’re unsure whether it needs to be replaced, you can always get a mechanic’s opinion.

Fuel odor

If your gas cap is creating a proper seal, you shouldn’t be able to notice fuel odors when standing near your vehicle.
If you do notice a fuel smell that seems to be coming from your vehicle, it could mean that fuel vapors are escaping from the fuel tank. As a result, the gas cap may need tightening, or you may need to look for signs of a leak somewhere else in the system.

Dirt buildup

Resolving your fuel inlet warning light can be as simple as cleaning your gas cap and the area surrounding the fuel inlet—which is something you’ll want to do periodically as a car owner. 

Vacuum pressure leak

A loose or damaged gas cap can cause a vacuum pressure leak, making it more difficult for fuel to flow properly through your vehicle’s system. 

EVAP leak

If an EVAP system leak is the cause of your check fuel inlet light, it’s possible your check engine light may also come on at the same time. An onboard diagnostic scanner (OBD-II) can be useful in detecting an EVAP system leak.
The fix to an EVAP system leak could be as easy as tightening your fuel cap. In some cases, however, there may be leaks in or damage to other components that may require replacement, in which case it’s best for a mechanic to take a look.
Let Jerry find your price in only 45 seconds
No spam · No long forms · No fees
Find insurance savings

How to check your fuel fill inlet

How do you inspect your fuel fill inlet for problems? You’ll need to carefully examine the gas cap and seal, the fuel door, and the fuel inlet
Look for signs of leakage, cracks, or other types of wear. Even if you discover an issue that seemsminor, it’s possible that it could still be enough to let gasses escape the fuel tank and trigger your check fuel inlet light.
If you’ve noticed any obvious signs of damage, replace or repair the damaged parts as necessary. You might be able to find a suitable replacement gas cap at an auto parts store, while a mechanic may need to take care of more complicated work, like replacing a fuel inlet, for you.

When to take your car to a mechanic

If you’ve inspected your car’s fuel fill inlet for problems but still can’t figure out why your warning light is on, you may need to take your car to a mechanic to find out the cause of the problem. 
It’s not a fix you’ll want to put off for long. If an opening in your fuel system allows dirt and debris into your fuel tank, you may have to make more expensive repairs to your vehicle further down the road.
You might especially want to visit a mechanic if you notice symptoms like:
  • Rough idling
  • Engine stalling
  • Declining gas mileage
  • Worsened vehicle performance
Granted, these issues can also be related to a number of other problems with your vehicle. A certified mechanic can help you determine the underlying cause and the proper fix.
One issue you definitely don’t want to delay addressing?A fuel leak. Since fuel is highly flammable, you’d be taking a considerable fire risk wherever you drive, putting you and others around you in danger. 
If you’ve discovered your car is leaking fuel, you should stop driving your car immediately and consult a mechanic for the next steps. You’ll likely need to have your vehicle towed to an automotive repair shop for repairs.

How to find affordable car insurance

Figuring out your car troubles can feel tedious—but shopping for better
car insurance
doesn’t have to be.
At least, not with the
Jerry
app. With Jerry, it only takes about 45 seconds to answer a few basic questions—like the level of coverage you’re looking for—to instantly start comparing competitive quotes from some of the nation’s top providers, all in one spot, right at your fingertips.
From there, you can choose the right amount of coverage for you at the right rate. Once you’ve made your pick, we’ll even help you make a smooth switch to your new provider.
Even better, drivers who switch with Jerry save over $800 per year on their car insurance!
“Insurance companies originally charged me $189 while driving my BMW 300 miles per year. Thanks to
Jerry
, I only pay $56! I’m so happy.”  —Ray T.
RECOMMENDED
Put your insurance shopping on auto-pilot NOW and save money automatically every 6 months
New quotes when prices drop automatically
30 seconds to sign up
No phone calls or people bothering you
100% FREE
Get started now - select insurance you want to put on auto-pilot:
rating primary
Rated 4.7 based on over 600 reviews

FAQs

The severity of the check fuel inlet warning light depends on what’s causing the problem. In some cases, the fix could be as simple as replacing your fuel cap. However, the more severe issues, like a leak in the fuel system, could require immediate attention from a mechanic.
Once the problem causing your check fuel fill inlet is addressed, the warning light should turn off automatically. Sometimes disconnecting and reconnecting your battery after making the proper fix can help reset the light.
If it remains on, there could be an existing problem elsewhere, like a system leak or faulty FTP sensor.
If you’re unsure why your check fuel fill inlet remains on, it’s best to take your vehicle to a mechanic.
It depends on the reason the light is on.
Estimate your repair costs for free with GarageGuard™
Simplify your car maintenance with Jerry.
Try GarageGuard™

Easiest way to compare and buy car insurance

√
No long forms
√
No spam or unwanted phone calls
√
Quotes from top insurance companies
Find insurance savings