Check Fuel Fill Inlet – What Does It Mean & How To Fix It?

If you see a "check fuel fill inlet" message on your car's dashboard, don't panic. Here's what it means and how to fix it.

Check Fuel Fill Inlet

Your dashboard has many warning lights that let you know when something is wrong. So, what does the “Check Fuel Fill Inlet” message mean? Is it just meant to scare you into visiting the mechanic or should you take the alert seriously?

In this guide, we evaluate the warning message and let you know what could be wrong. We also go on to explain the fuel fill inlet, so you can better understand your vehicle. At the end of the guide, we discuss possible repair costs and let you know if you should keep driving your car.

What Does the “Check Fuel Fill Inlet” Message Mean?

The dashboard warning message indicating “Check Fuel Fill Inlet” means that something is wrong with the evaporative emissions control system (EVAP) that is causing a leak. It could be something as simple as a loose gas cap or contamination that needs to be cleaned.

The Evaporative Emission Control System (EVAP) prevents gas vapors from escaping from the fuel tank. These systems have been required on all gasoline-powered vehicles since back in the 1970s and are made from several components that work together in harmony.

What is Fuel Fill Inlet?

The fuel fill inlet is where the fuel gets fed into the gas tank. It is topped with a gas cap that covers the inlet. 

With most cars, this inlet is determined by both the gas cap and the tube leading into the tank. Without this inlet, you wouldn’t be able to get fuel into the tank so it could run. 

Reasons for Check Fuel Fill Inlet Warning

1. Fuel Cap Missing

If you fail to put the fuel cap back on the tank, you will probably see the Check Engine Light come on. It can also cause the “Check Fuel Fill Inlet” message on the dashboard. Because of the modern sensors on today’s cars, you can expect to see some warning if the cap is missing.

Thankfully, fuel shouldn’t spill out as a result of the missing cap. Still, the system is meant to be closed and it’s not with the cap open. To fix the problem, all you need to do is put the cap back on and viola, it’s repaired. 

2. Unsecured Fuel Cap

Maybe you put the fuel cap on, but it didn’t click all the way. In this case, you could also receive either message on the dashboard. 

With the cap off slightly, the pressure in the system won’t be right. Before you pull away from the gas station, ensure that the cap clicks in place so you know it’s properly tightened. 

There’s also the chance that the cap is loose because of damage. If you can’t get it to click, you might need to replace it with a new one. Any damage to the gas cap should be taken seriously. With the low price of a new cap, there’s no reason to procrastinate with the fix. 

3. Overtightened Fuel Cap

To counteract the loose fuel cap, you might go ahead and overtighten it, but this isn’t a good idea either. The cap is fitted with silicone material and rubber gaskets to ensure a proper seal.

When you tighten it too hard, these parts can break or fail. Any damage to the sealing function can lead to vapors escaping, which causes the warning light to come on. To repair it, you’ll still need a new gas cap. 

4. Dirt Contamination

Even if you are diligent about cleaning your car and keeping it in good condition, there’s probably one area you neglect. The fuel filler neck is the opening where you fill-up the gas tank. It’s a spot that seems to collect dirt quite easily but never seems to get cleaned out. 

If the fuel filler neck or inlet becomes contaminated, it can stop the cap from sealing and lead to other malfunctions. As the buildup becomes worse, you could also see the Check Fuel Fill Inlet warning. Beyond that, dirt that’s allowed to sit on the components can eventually lead to breakdown or corrosion of the parts. Do yourself a favor and clean the area out with a rag when you are washing your car. 

6. Evaporative Emission Control System (EVAP) Leak

If there’s a leak in the EVAP system, you may see both the Check Engine Light and the Check Fuel Fill Inlet message. To determine what’s going on, you want to use your code scanner for better insight. Trouble codes P0455 and P0456 both indicate a sign of an EVAP leak. 

However, these leaks can be caused by something as small as a contaminated or broken gas cap, as we mentioned above. Still, you don’t want to overlook the chances of a broken EVAP system component. In general, an EVAP leak isn’t going to lead to major trouble with the car, but you should still take it seriously. Not only is the car pumping out gases that hurt the environment, but you can also fail an emissions test until you have it fixed. 

The best way to find an EVAP leak is to use an EVAP smoke machine.

RELATED: What is an EVAP Leak? (& Is it Safe to Drive with?)

How to fix “Check Fuel Fill Inlet” on Ford

While you can find the “Check Fuel Fill Inlet” message on some different car brands, the most common car model you will find it on is Ford vehicles. There is also a reason why you will find it on these models, and that’s because of the capless gas tank that these car models often use.

Instead of a normal gas cap that you remove before refilling fuel, these cars have a flap valve that seals the gas tank instead of the standard gas tank. Unfortunately, if this flap valve gets dirty or worn, it won’t seal properly, and you will see the check fuel fill inlet message on your dashboard.

Some of the affected models are:

  • Ford F150
  • Ford Edge
  • Ford Fusion
  • Ford Escape
  • Ford Explorer
  • Ford Mustang

You may find this message on more Ford models, but these are the most common.

If you have a Ford vehicle with a capless gas tank and see the “Check fuel fill inlet” message on your dashboard, you need to clean and lubricate the gas tank flap.

Look at the gas tank flap and press it with a screwdriver or something similar. Be careful so that you don’t drop it into the gas tank. Clean the sealings from any dirt around the sealing area and spray some lubricant. Open and close the flap a couple of times. By doing this, you can often get the flap to seal better, and that may be enough to fix the message.

Cost to Repair Check Fuel Fill Inlet Message

The cost you encounter to repair the Check Fuel Fill Inlet message could be anywhere from $5 to $1,000+. It’s difficult to estimate what you are up against because a complete diagnosis is needed first.

Obviously, if there’s a problem with the gas cap, this will be your least expensive repair. Even if the cap is simply dirty, you are looking at a fix that’s essentially free.

On the other hand, if you have a vacuum leak to deal with, you could spend a lot of money between diagnosing and repairing it, especially if you need help from a certified mechanic. For this reason, we encourage you to do your research ahead of time to determine what’s causing the problem. If it’s something you feel confident repairing on your own, you might as well save the labor cost. 

FAQs about the Check Fuel Fill Inlet message

Can I Drive With A Check Fuel Fill Inlet Message?

Most of the problems that cause this message to come on aren’t severe. For this reason, you don’t have to stop driving immediately. However, you should always have faults looked at and repaired as soon as possible to ensure the rest of the car continues running as intended. 

What’s more alarming is what could happen while these messages remain on the dashboard. If another component were to fail while the Check Engine Light was on, you wouldn’t know what’s happening. Something major could happen and you would keep driving, which isn’t wise. For this reason alone, we recommend resolving the issue and getting the warning lights off of your dash, so you can remain informed.

Why do new cars have no gas cap?

The idea behind a capless fuel system is that it makes refueling your car faster and less messy. The fuel goes into a sealed tank with a valve that only opens when the nozzle from the pump is inserted. This helps to prevent the evaporation of gas fumes, which can pollute the environment. However, these capless gas tank inlets do unfortunately sometimes fail.

Can you put a cap on a capless gas tank inlet?

It depends on the car model, but you can actually find aftermarket gas caps that will fit the capless gas tank inlet on your car model. You can also make one yourself, but it may require some basic skills, and it is much easier to buy one that is custom made for your car model.

How do I reset the check fuel fill inlet message?

The easiest way to reset a fuel check message is to use an OBD2 scanner. Just connect the scanner and clear the error code memory. But if you didn’t fix the problem that caused the message in the first place, the warning light will return sooner or later. Depending on the car model, it can also reset by itself if you solve the issue and let the car make a couple of successful test cycles, but it may take a while.