OK guys. Try to keep the falming to a minimum, but just 2 hours I made the feminine mistake of driving home from a gas station with my fuel door open and the gas cap sitting on the back of the car. When I pulled up and got out of the car was when I noticed the fuel door open, and was like oh crap my gas cap just caught the midnight train to Georgia. I went back to the station, which is about a 60 second drive from my house, and retraced my steps to no avail. I'm going to look again tomorrow when It's light outside, but if I don't see it I'm SOL. I have been procrastinating getting a locking gas cap for awhile now, and here is the perfect excuse. But here's the problem: I don't get paid til friday. And with shipping times it will probably be close to 2 weeks before I have a gas cap again! What sort of adverse affects are we looking at here going for so long without a gas cap? Don't give me any yahoo answers BS about fuel magically climbing It's way up the fuel neck and spilling out on the road, especially with the little trapdoor on the inside of the neck.

It will evaporate out more easily.

Be glad you didn't have a locking gas cap. It would simply mean that you had lost a more expensive one!

It is very important to have a gas cap. Some people have had problems with gas coming out even with a gas cap, including me. They only cost about $10. I collect them from JY cars, so I have six extras, if you want one let me know...

That'd be great but I can't afford an arm and leg for shipping.

That's what I was afraid of. A Google search turned up answers like fuel "spilling" out onto the road and problems with the fuel system pressure, which didn't make sense to me.

It got real silly when people tried saying one of the risks was getting your tank sugared or siphoned, which could happen just as easily by unscrewing an existing gas cap

I don't think our cars are supposed to maintain any pressure in the gas tank. Evaporation shouldn't be that much of a problem. If you are really worried about it and don't mind feeling a like a *******, you could put a piece of tape over the end of the filler neck. My biggest worry would be things entering the gas tank.

With the trapdoor on the entrance to the tank neck, I'm not too worried about anything entering the tank.

I am a b it concerned now about you saying our cars not being designed to hold any pressure in the tank. Whenever I stop for gas and go to take the gas cap off, most of the time the tank releases pressure when I unscrew it. Not an outrageous amount about to blow the cap out of my hand, but enough to emit a noticable hissing sound.

gas evaporates pretty fast, and its bad for the environment. id be interested to see the math of petrolium evaporation rate in an open container until pay day vs the cost of fuel vs the cost of a fuel cap.

OUR systems are supposed to be pressurised . To keep crap out of it might try a baggie and rubber band or steal a neighbors.

Couldn't you just go to AutoZone or NAPA to get a new locking cap? No need to wait for shipping that way.

i concur...
autozone, napa, pep boys, advanced, ect...
they should all have generic locking gas caps.
if you were really anal about it you could have the lock matched to your existing exterior locks, or if you were smart, you would have it matched to your ignition key so that you couldnt get the cap off with the engine running

Yep, get one at the local parts store, but you need to know if you need vented or not. This I don't recall, but there's usually a chart nearby to find the right one. IIRC, it depends on if it's FI or not?

Relax. Everyone is missing the boat.
People leave their gas cap sitting on the gas pump all of the time. Stop by a few convience stores and tell them you left your cap there. They will pull out a drawer full of caps to choose from.
Just pick one, they're free.