Does the gas tank have a metal cap covering the hole?
 

It does right? I filled up the other day and noticed it was missing but the dealer said it doesn't have one. I do drive my girlfriends MR2 and my 1st gen celicas from time to time so maybe I am mixing information up.

Could anyone verify this for me?

Ehhhh, I don't remember any metal cap.

No, it never had any. Because race car..

you mean like a little spring door on the inside of the tank?

Should have elaborated more. So you pop the tank, pop the plastic cap, and the spring loaded metal cap where you put the pump into. I know my older cars have it so I don't know if I am just assuming it has one out of association haha.

I believe your on to what I am talking about.

i know my camry has it but i really dont recal ever seeing it on the frs.

edit: so just ran to the garage to check for you. mine dont have the little door. so either i have same issue as you or the frs just dont have those things. im betting on the latter

Thanks man, I was going crazy like, Does it have one? haha

My (very) old Toyota Paseo has the metal cap, my european GT86 doesn't.

because saves weight ;)

It's probably located further down the "neck" of the fuel tank. If I remember correctly it HAS to be there by law to prevent fumes from escaping the tank, they figured out in the 80's that the fumes that were being emitted while filling up and letting a gas tank "breath" were incredibly damaging to the environment so they came up with systems to trap them.

Now when you fuel up that big rubber donut creates a seal which channels the fumes in your empty tank to the tank under the gas station as your tank gets filled up, same thing happens when the gas station gets their tanks refilled and then the fumes get transported back to the refinery. Not sure what happens to them if they're re-processed into something or just disposed of in a less damaging way to the environment than venting to the air.

WTF. How high are you? :slap:

High enough to have taken classes on engines and gotten a relevant degree to the topic (mechanical engineering).

[ame="http://en.wikipedia.org/wiki/Onboard_refueling_vapor_recovery"]Onboard refueling vapor recovery - Wikipedia, the free encyclopedia[/ame]
http://www.arb.ca.gov/vapor/vapor.htm
http://usatoday30.usatoday.com/money...on-fumes_n.htm

Looks like you live in a state that doesn't require vapor recovery systems (the proper name escaped me for my initial post) so I'm not surprised you are surprised by this information.

Well thanks for teaching me something new today. You are right, apparently FL doesn't require this as I have never seen it. Feel free to slap me back :D

This I didn't know, I knew its purpose but didn't know it was a regulation.

My post kind of strayed into the refueling component but the basis of the regulation is to prevent fumes from escaping the tank and polluting the atmosphere. There is probably some form of pressure relief in an emergency so the tank doesn't balloon up but for the most part tanks are sealed.

Yeah, modern fuel systems are sealed but the gas cap has a safety release that goes at a certain pressure. I know that because my other car would vent there eventually.
I know a some of cars now don't even have a screw on gas cap anymore.

It is no longer required, since we will get a check engine light if we leave the gas cap off. That was also designed so you couldn't put a larger diameter leaded gas nozzle just into the filler neck and gravity feed the tank. It required you to push the narrower unleaded nozzle in the neck in order for fuel to flow. I don't think there is leaded auto gas anymore, so the flapper valve is no longer necessary.

John