# 2012 Kia Forte - Gas cap issue **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** kia\ **Created:** [April 27, 2022, 2:01am UTC](https://community.cartalk.com/t/2012-kia-forte-gas-cap-issue/183841 "2022-04-27T02:01:27Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![frotch](https://avatars.discourse-cdn.com/v4/letter/f/c6cbf5/32.png) [@frotch](https://community.cartalk.com/u/frotch)\ **Post date:** [April 27, 2022, 2:01am UTC](https://community.cartalk.com/t/2012-kia-forte-gas-cap-issue/183841/1 "2022-04-27T02:01:27Z")
did u have to replace the gas cap in u’r 2012 kia forte light was on told me evap system tightin cap light goes off then comes on what can i have wong with it ---
**Author:** ![Purebred](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/purebred/32/46796_2.png) [@Purebred](https://community.cartalk.com/u/Purebred)\ **Post date:** [April 27, 2022, 1:45pm UTC](https://community.cartalk.com/t/2012-kia-forte-gas-cap-issue/183841/2 "2022-04-27T13:45:01Z")
More curious about what you are using to translate from your native language to English. You post is nearly unreadable. Please ask someone to help you compose the question, including with **all** pertinent data, then translate into English. ---
**Author:** ![shanonia](https://avatars.discourse-cdn.com/v4/letter/s/9de053/32.png) [@shanonia](https://community.cartalk.com/u/shanonia)\ **Post date:** [April 28, 2022, 12:15am UTC](https://community.cartalk.com/t/2012-kia-forte-gas-cap-issue/183841/3 "2022-04-28T00:15:16Z")
Sometimes the check engine light comes on because there’s a leak in the evaporative control system. Sometimes it’s as simple as the gas cap not on tightly enough. Sometimes a new cap will seal better and the leak is fixed. ---
**Author:** ![davepsinbox\_157004](https://avatars.discourse-cdn.com/v4/letter/d/73ab20/32.png) [@davepsinbox\_157004](https://community.cartalk.com/u/davepsinbox_157004)\ **Post date:** [April 28, 2022, 12:34am UTC](https://community.cartalk.com/t/2012-kia-forte-gas-cap-issue/183841/4 "2022-04-28T00:34:34Z")
Let’s see if I understand. Your check engine light came on and you had the code scanned and it came back as a problem with the evaporative emissions system. Someone suggested replacing the gas cap. You did that and the light went off but then came back on. Does that sound about right? You need to take it to someone who can figure out what’s wrong instead of guessing. And hats off to shanonia for giving a _constructive_ answer. ---
**Author:** ![lion9car](https://avatars.discourse-cdn.com/v4/letter/l/59ef9b/32.png) [@lion9car](https://community.cartalk.com/u/lion9car)\ **Post date:** [April 28, 2022, 6:15pm UTC](https://community.cartalk.com/t/2012-kia-forte-gas-cap-issue/183841/5 "2022-04-28T18:15:58Z")
> [@davepsinbox\_157004](#): > > And hats off to shanonia for giving a _constructive_ answer. There’s nothing wrong with Purebred pointing out that the question was very hard to read. I personally skipped it because I won’t bother helping someone who doesn’t make it easy for me to do so. ---
**Author:** ![db4690](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/db4690/32/2583_2.png) [@db4690](https://community.cartalk.com/u/db4690)\ **Post date:** [April 29, 2022, 8:38pm UTC](https://community.cartalk.com/t/2012-kia-forte-gas-cap-issue/183841/6 "2022-04-29T20:38:55Z")
Some cars actually have a “missing fuel filler cap” image and/or warning lights I personally don’t like these . . . because it makes people assume the fuel filler cap is the problem, when the evap leak may be something completely different, such as a rotten fuel filler hose, for example It leads some people to think diagnosis isn’t required ---
**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\ **Post date:** [May 7, 2022, 9:19pm UTC](https://community.cartalk.com/t/2012-kia-forte-gas-cap-issue/183841/7 "2022-05-07T21:19:58Z")
Maybe a brief explanation of how it works would be helpful for the OP. The space above the liquid gasoline in the gas tank contains fumes that the EPA requires must be burned in the engine. That system is supposed to be leak free, holding the fumes (partly using the canister) until a purge valve opens and directs the fumes into the engine. A computer is constantly checking that there’s no other path for leaks. Every car does that differently, but if there is a leak detected it’s likely one of these - Gas cap - Various hoses between tank and canister - Purge valve failing - Vent valve failing - Charcoal canister failing - Fuel tank connection leaking - Pressure sensor failing (means there may not be an actual leak, just a failing sensor) Diagnostic codes will provide a clue to what’s wrong, but each possibility will still have to be tested by the shop. Since there’s a gas cap suspect, OP could try rubbing a thin film of engine oil on the gas cap o-ring gasket, might produce the required seal.