Common Causes of Faulty Gas Caps

In one of our recent blogs, we mentioned that a faulty, loose, or damaged gas cap could trigger your check engine light to come on your dash. Most people assume it is no big deal and shrug it off, but this is a huge mistake. If your gas cap is causing problems, it is not something you should delay replacing. It can allow dirt and grime to escape into your vehicle’s fuel system, and it can allow fuel fumes to escape.

What Are the Causes of Faulty Gas Caps?

Unsecured Cap - While this problem is technically damage-free, you should fasten your gas cap ASAP. This problem happens after someone fills up their tank and forgets to fasten it or neglects to tighten it enough.
Broken Cap Seal - Gas cap seals keep the fuel in the tank pressurized and closed off completely. When the seal is worn, it can cause a leak in pressure.
Wrong or Poor Gas Cap Installation - It may be a surprise, but gas caps are not universal. If you installed an ill-fitting one, it could cause your check engine light to come on.

How to Tell If You Have a Faulty Gas Lid

As mentioned, a check engine light will illuminate your dashboard when your car’s computer detects a discrepancy with the fuel lid. Besides physically inspecting the lid for a leak, you can confirm whether it is the problem behind your check engine light by performing a scan. You can use your own scan tool or bring your vehicle to Toole’s Garage for a check engine diagnostics. The trouble codes P0440-P0443, P0446, P0453, and P0455-P0456 are commonly linked to a damaged gas cap.

If you need a gap cap replacement, please call or visit the professionals at Toole's Garage in Stockton today.

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