Fuel Caps Get No Respect

The lowly fuel cap doesn’t often get the love and respect that it should. In fact, it might be the only important part of a car to find itself forgotten in a gas station parking lot. Although a bit surprising, today’s cars actually have several barriers to keeping gasoline from physically splashing out. However the fuel cap still plays an important role in being “kept” and used properly - beyond the obvious.

First off, the fuel cap keeps dirt and water out of the fuel tank. Leave your fuel cap behind at the gas station on a rainy day and this could seriously mess up your engine. This is because water ending up in the fuel tank doesn’t burn like fuel does when it hits the engine. Dirt is another problem in that it will easily clog up the fuel filter and carry harmful particulates to the engine. Fastening your fuel cap properly after a fill-up and not leaving it behind is your best defense in keeping these unwanted issues from happening.

Your fuel cap not only keeps harmful items out of the gas tank, but also keeps fuel vapors in. It is an important part of your evaporative emissions control system, or (EVAP), that keeps fuel vapors from escaping into the atmosphere; which is both bad for fresh air, but also bad for your wallet. Did you know a loose gas cap can allow up to thirty, that’s 30, gallons of fuel to escape per year! If you do the math, you’ll realize that the economy of replacing your fuel cap right away – if lost or left behind - is a no brainer.

Now that you know the importance of your fuel cap, why are we making such a big deal out of talking about it? That’s because a worn or loose fuel cap can be the reason your check engine light is on. There’s also a chance you can fail an emissions test if your fuel cap is worn.

If your check engine light is on and you’re due for an emissions test, be sure to stop in a neighborhood NAPA AutoCare location right away. We can run a diagnosis and it might just be that fuel cap causing the issue.

Posted May 19th, 2016