Replacing Fuel Cap With Clip-In Tank: Easy Diy Guide

A fuel cap is an essential component of a vehicle's fuel system, serving several important purposes, including preventing impurities from entering the fuel tank and stopping fuel fumes and spills. When a fuel cap fails, it can lead to contaminated fuel, failed fuel system parts, and fuel leaks, posing a safety hazard. Therefore, it is crucial to recognise the signs of a failing fuel cap and replace it as soon as possible. This process typically involves removing the old cap, inspecting it for damage, and installing a new cap, ensuring it is securely sealed. While the steps may vary slightly depending on the vehicle model and type of gas cap, it is generally a straightforward task that can be completed within a short time.

Identify the type of gas cap

Identifying the type of gas cap your vehicle requires is crucial for ensuring optimal performance and preventing fuel leaks. Here are some steps to help you identify the correct type of gas cap:

Check the Make, Model, and Year of Your Vehicle

The type of gas cap needed varies depending on the make, model, and year of your car. Refer to your vehicle's information to narrow down the options.

Consult the Owner's Manual

Your car's owner's manual is a valuable resource. It should provide detailed information about the specific fuel cap fitting type and may even include instructions on how to replace it.

Observe the Colour of the Fuel Cap

The colour of the fuel cap indicates the type of fuel your vehicle uses. Black fuel caps are typically for gasoline with less than 10% ethanol content, green caps indicate diesel fuel, and yellow caps signify flexible fuel vehicles that use gasoline with 15-85% ethanol content.

Determine the Fitting Type

Gas caps can have internal or external fittings. Some require screwing into place, while others have aligning components that fit into the filler tube neck. Check your current fuel cap to identify the fitting type.

Consider Additional Features

Decide if you want a locking gas cap for added security or a tethered cap to prevent loss. These features provide extra functionality and convenience.

Check with Auto Parts Specialists

If you're still unsure, consult professionals at auto parts stores or dealerships. They can guide you in choosing the correct gas cap based on your vehicle's specifications.

Remember, choosing the right gas cap is essential not only for efficient fuel system operation but also for maintaining proper emissions control and preventing fuel leaks.

Remove the old gas cap

To remove the old gas cap, start by locating the fuel filler cap. Open the fuel door to gain access to the gas cap. Check the gas cap for any exterior damage. Remove the gas cap from the filler neck and disconnect the cable from the fuel door.

If your gas cap has a leash, you will need to remove that as well. Locate the locking peg attached to the leash and pop it out of the hole in the fuel door. Press up on the bottom of the locking peg until it unsnaps from the door hinge.

If your gas cap has a lock, insert the key into the keyhole and turn it in a counter-clockwise motion to unlock the cap. Hold the cap still as you turn the key. For pre-vent (pressure release) locking caps, allow the pressure to release before removing the cap. Listen for the sound of hissing and wait for it to stop completely. Then, continue turning the cap counter-clockwise until it is completely loose.

Once the cap is loose, lift it away from the filler neck and set it aside. Keep the old gas cap until you have installed a new one. If the new cap does not fit your fuel tank for some reason, you can use the old cap to cover the fuel tank opening until a better replacement is found.

Check for damage

To check for damage to your fuel cap, there are several things you can look out for. Firstly, if you notice a strong smell of gasoline or diesel vapours around or near the fuel filler cap, this could indicate that the cap is damaged and is no longer preventing vapours from escaping.

Secondly, if you are finding it difficult to open or close the fuel cap, this could be a sign of damage. This may be due to continuous exposure to dust and rust, or it could be the result of excessive pressure applied when trying to open or close the cap, which can cause the internal parts to malfunction.

Thirdly, if the cap does not feel tight when closed, this could be a sign that the cap is damaged and not sealing properly. This can lead to leaks of vapour and fuel, which will affect fuel consumption and car performance.

Finally, if the "Check Engine Light" illuminates on your dashboard, this could be due to a problem with the fuel cap. This issue can often be diagnosed using a car error scanner, which will give an error code associated with the problem.

Install the new gas cap

Now that you've removed the old, faulty gas cap, it's time to install the new one. This process is relatively straightforward and can be done in a few simple steps.

Firstly, if your new gas cap has a leash, unwind it by rotating it in a clockwise direction around the cap. This should be easy to do and will allow you to connect the leash later. It is recommended that you purchase an original manufactured equipment (OEM) cap, as these are designed specifically for your vehicle.

Next, connect the leash by pressing the locking peg into the hole in the door of your fuel tank. You should find this hole near the hinge of the door, and it may make an audible "snap" as it locks into place. If your vehicle does not have a hole for the leash, you will need to use a gas cap without one.

Now, insert the gas cap into the opening of the fuel tank and rotate it clockwise until it feels secure and tight. You should either hear a "click" or feel that the cap will not move any further.

If you have a pressure release and quick-on locking gas cap, you will need to insert the key and turn it counter-clockwise to unlock the cap. Then, rotate the cap to the right until you hear three clicks, indicating that the cap is secured.

For a metal push-on locking gas cap, simply push the cap directly into the filler neck of the fuel tank until you hear a click. Do not turn the cap as this may damage it. Instead, test it by wiggling it slightly to ensure it is secure.

Once your new gas cap is in place, you can start the engine and take your vehicle for a test drive. Go over different terrains and drive at varying speeds to ensure the gas cap holds. Monitor the dashboard for any warning lights, and if the engine light comes on, you may need to get the fuel system checked for electrical issues.

Test the new gas cap

Once you've replaced your fuel cap, it's important to test it to ensure it's working correctly. Here are some ways to do that:

Check for a Tight Seal

Make sure the new gas cap is tightly sealed. Most gas caps are sealed by turning them until you hear a clicking sound. Some gas caps have a ratcheting mechanism that requires you to turn the cap until it clicks closed or refuses to move any further.

Test the Cap by Trying to Loosen It

Try to turn the cap to the left. A properly installed gas cap shouldn't budge. If it can be easily turned, it may not be installed correctly or could be defective.

Check for Warning Lights

After installing the new gas cap, take your vehicle for a test drive. Drive over different types of terrain, such as bumpy roads, to allow the fuel to slosh around inside the tank. This will create fuel vapors and help you identify any leaks. Monitor the dashboard for warning lights, such as the check engine light, which could indicate a problem with the gas cap or the fuel system.

Check for Fuel Vapors

Use a combustible gas detector to verify that there are no fuel vapors leaking from the gas cap or the fuel filler neck. Fuel vapors are highly flammable, so it's important to ensure there are no leaks.

Check the Gaskets

Inspect the gasket on the bottom of the fuel cap for any cracks or distortions. A damaged gasket can cause fuel vapors to escape, leading to potential safety and environmental hazards.

Check the Filler Neck

Examine the fuel filler neck for any damage. If you notice any issues, the filler neck may be failing, which could affect the performance of the new gas cap.

Check the Vehicle's Performance

After installing the new gas cap, pay attention to how your vehicle performs. A faulty gas cap can cause a drop in fuel economy, so monitor your fuel consumption to see if there are any significant changes. Additionally, be aware of any unusual smells, such as the distinct smell of gasoline or vapors, which could indicate a leak.

Frequently asked questions