Does anyone know if our gas caps are supposed to be vented or not. My OEM gas cap is so loose that gas sloshes out after I fill it up and take some twisty roads. The original cap looks like it may be vented?! I have a non-vented cap that fits and seals great but creates one heck of a vacuum. TIA

 

The cap in my '85 is non-vented. When I use up 1/2 tank or more between fillups I can hear it suck in air when I pop the cap.

I looked into a replacement cap as mine is a bit corroded (just cosmetic stuff) and of all the vented/non-vented ones listed the only one supposedly "for" my car was a non vented one. Then again it was $2 when all the rest were $7.50

 

My 82 is not vented.

 

non vented. sounds like your seal's toast or something's bent.

 

yeah, the seal was toast. The new cap seals real well. Funny thing is my old cap passed NJ state inspection. During inspection they put the cap on some sorta gizmo that tests it. I dunno.....

 

they are non vented on the 12a models.
when I put on an aftermarket gas capit must have had a bad seal because my charcoal canister became clogged. I bought a new cap from mazda and a new canister and have had no problems since.

 

Mines non-vented, but it leaked like a *****. So bad infact, that the gas made the trim on that rear quarter fall off . Anyway, it turns out that mine had a torn gasket that took me about a week to notice. I just grabbed one off of my 84 parts car and Im good now .

~T.J.

 

I bought a locking gas cap for my 85 GSL, it's not vented. It's kinda hard to take off if you run through a whole tank.