How To Install a Locking Gas Cap | YourMechanic Advice

How To Install a Locking Gas Cap

Gas caps can fail due to a number of reasons. A leaking fuel cap can lose you upwards of 2% of your gas from evaporation.

Gas caps get cranked on week after week, month after month, and year after year. They leak around their seals, the threads can become damaged, and the ratcheting mechanisms can fail — just to name a few of the most common issues. Most states have emissions testing standards that test the amount of evaporation coming from gas caps.

Severe leaks in the gas cap cause the fuel pump and engine to work harder than usual. The harder the engine works, the more exhaust fumes are sent into our environment, causing additional damage.

Use one of the following procedures to replace a failed or leaking gas cap on your vehicle.

Part 1 of 2: Install a locking gas cap

Material Needed

Step 1: Buy a locking gas cap. When upgrading or replacing a gas cap, purchase a locking cap for your vehicle. This type of fuel cap can be found at automotive stores or online.

Gas caps are necessary for proper gas tank function. If the fuel cap on your vehicle is missing or broken, replace it immediately. Fuel efficiency can vary depending on the quality and the seal on your gas cap.

gas cap leash connection to the vehicle body

Step 2: Secure the cap leash. Replacement caps often come with a “leash” or plastic ring that keeps the cap from being lost. Secure the cap leash with its peg on the vehicle side of the leash.

pressing new cap into place

Step 3: Press the new cap in place. Press the new cap flush against the fuel filler neck thread and rotate clockwise until it “clicks” into place. The audible click verifies that the cap is sealed.

  • Note: Never force anything into place on your vehicle. A new cap should screw easily into place without any serious resistance.

Step 4: Put the key into the gas cap. Insert the key into the gas cap and rotate it clockwise to engage the locking mechanism.

  • Note: Always test the gas cap and ensure that its locked. Most caps swivel and do not engage the threads while the cap is opened.

Part 2 of 2: Install a non-locking gas cap

Materials Needed

Step 1: Buy a replacement gas cap. Replacement gas caps can be found at automotive stores or online.

securing the gas cap leash

Step 2: Secure the cap leash. Replacement caps often come with a “leash” or plastic ring that keeps the cap from being lost. Secure the cap leash with its peg on the vehicle side of the leash.

Step 3: Press the new cap in place. Press the new cap flush against the fuel filler neck thread and rotate clockwise until it “clicks” into place. The audible click verifies that the cap is sealed.

  • Note: Never force anything into place on your vehicle. A new cap should screw easily into place without any serious resistance.

Gas caps are a critical part of your fuel system. If you need to replace the gas cap on your vehicle, buy a replacement gas cap with a lock. Replacing it is as simple as connecting it and screwing it in.

If you need assistance in replacing your gas cap, contact a professional mechanic, such as one from YourMechanic, to do it for you at your home or office.


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Recent Gas Cap Replacement reviews

Excellent Rating


YourMechanic Gas Cap Replacement Service

Average Rating

4.6/5

Number of Reviews

40

Rating Summary
33
2
2
1
2
33
2
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Brian

22 years of experience
406 reviews
Brian
22 years of experience
Chrysler PT Cruiser - Gas Cap - Jacksonville, Florida
Competent and kind. He understood my difficulties hearing and made adjustments so that I would understand what he had done and what would need to be done/checked in six months. I will ask for him again and I will recommend your company based upon Brian's professionalism.
Chrysler 200 - Gas Cap - Jacksonville, Florida
Brian listened to all the concerns I had with my car, he seemed very knowledgeable , and he also got the job done pretty quick.

Nolan

29 years of experience
51 reviews
Nolan
29 years of experience
Kia Rio - Gas Cap - Tucson, Arizona
Nolan was prompt, professional and took the time to answer all of my questions. This service was very easy to use!

James

29 years of experience
690 reviews
James
29 years of experience
Toyota Corolla - Gas Cap - Orlando, Florida
James is the best you can get! Not only does he fix everything he lets you know if you have any other issues and even shows you how you can fix it yourself. He's amazing and always has something interesting and fun to say. He knows how to hold a conversation and if you have a question he definitely has an answer. He's sweet and good hearted. His hard work doesn't go unnoticed. You will definitely love him! He's definitely my favorite of anyone I've ever had service my car!

Joe

14 years of experience
408 reviews
Joe
14 years of experience
Audi S4 - Gas Cap - Nashville, Tennessee
Once he arrived he stayed to give a thorough inspection and possible options for car (our need could have been other things as well). Had the right part. Definitely recommend Joe and recommend the service.

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