Stupid Tight Gas Cap Question...

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Our 195K Tundra King Cab gas cap gets really tight between fill ups. Don't drive it much. Truck is in super shape all around.
Probably original cap; looks fine.

Would a new cap help?

Thanks for your help.
 
There is a one-way valve to let air in as the tank empties. Possibly it isn't opening. The valve is located in the evaporation system near the fuel fill cap. Ed
 
Originally Posted by Eddie
There is a one-way valve to let air in as the tank empties. Possibly it isn't opening. The valve is located in the evaporation system near the fuel fill cap. Ed


Yeah, this. Does it give off a decent "whoosh" when you crack it?
 
The whoosh is not too bad. Surprising... I ordered a $5 Stant gas cap on Amazon.
I also Youtubed the evap valve; appeared to be near the gas tank.
I will post my results.
 
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My wife's LEXUS was the same way from new. I tried 2 other caps(3 including the OE) and it was still unbelievable to remove between fill ups, even after 15 years or ownership. I have strong hands and can remove the cap however it was even difficult for me.
 
Maybe the o-ring goes deeper into the filler neck than most models. You could put silicone or vaseline on it.

If the vaseline makes the rubber go bad, it's only $5 you're out.
 
Originally Posted by eljefino
You could put silicone or vaseline on it.

I was thinking Dielectric Grease. I use it on my rad cap. It's a bear to get off.
 
Sometimes what happens is the o-ring gets dirt or debris on it or imbeded in it.
If your filler neck is rusty, that stuff will get everywhere.

This can make the cap very hard to turn.

Try what others have suggested with the new cap and make sure the area is very clean.

A little dielectric grease on the o-ring may also help.
 
Most likely, the o-ring/gasket on your filler cap has flattened from usage. As a result, it keeps getting over tightened each time. A new cap should help.
 
I had an old car that had wrecked threads on the filler neck. I bought one of those gas caps that you leave on, and poke the gas filler nozzle through a spring loaded cover on the hole. Of course you have to make sure it stays clean. Some new cars come like that.
 
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Originally Posted by Warstud
Originally Posted by eljefino
You could put silicone or vaseline on it.

I was thinking Dielectric Grease. I use it on my rad cap. It's a bear to get off.


I did the dielectric grease thing too and it still didn't help.
 
Be careful with the cheap gas caps. I bought one from AAP, it was in a CarQuest box. Long story short, I filled up about 4 times, on the next fill, the cap would not come off!! After lots of trying, the top of the cap came off, leaving the bottom in the filler neck!! I drove to AAP to see if they could help, waste of time. After much work, I got some slip joint pliers to 'bite' on what was left of the cap and removed it. I insisted that AAP refunded the price. To fail after a month is soooooo bad.
 
I am having exact same problem with 2012 Acura TL; I have tried lots and lots of different chemicals but so far no luck. I have yet to purchase new OEM cap yet. I always think there is a miracle goop which fixes all my problems and I am forever search of such elixir :-(
 
Originally Posted by JeffKeryk
The whoosh is not too bad. Surprising... I ordered a $5 Stant gas cap on Amazon.
I also Youtubed the evap valve; appeared to be near the gas tank.
I will post my results.


hey jeffkeryk! I did the same thing with my scion tC (camry engine). The toyota seal wouldn't work well after 2-3 years, got tired of spending $25+ for a toyota cap. Got a stant cap, never had another problem! I think you'll be quite happy with the stant cap. Only issue was the stant didn't have a tether on the cap like the original.. Small price to pay for no more issues. Thought you'd like to know that a fellow toyota owner + stant gas cap = happy
thumbsup2.gif
 
Originally Posted by Warstud
Originally Posted by eljefino
You could put silicone or vaseline on it.

I was thinking Dielectric Grease. I use it on my rad cap. It's a bear to get off.

Dielectric grease is silicone grease and I would never use silicone anywhere near the fuel or intake systems. That stuff fouls sensors like crazy.
Better off using chassis grease or (what I use) a drop of motor oil.
 
Originally Posted by Vikas
I am having exact same problem with 2012 Acura TL; I have tried lots and lots of different chemicals but so far no luck. I have yet to purchase new OEM cap yet. I always think there is a miracle goop which fixes all my problems and I am forever search of such elixir :-(

Vikas, kick down with some of that magic elixir...
 
The cheapo $5 Stant cap seems to have done the trick.
I gassed her up at Costco and put on the new cap.
Drove to Petaluma (beautiful wine country) and back, maybe 180 miles.

Cap came off nice and easy; just like butta....
 
Originally Posted by JeffKeryk
The cheapo $5 Stant cap seems to have done the trick.
I gassed her up at Costco and put on the new cap.
Drove to Petaluma (beautiful wine country) and back, maybe 180 miles.

Cap came off nice and easy; just like butta....


hey I posted before in this thread.. I said then that I thought the stant cap would fix it. It did well on my scion (camry engine) tC.. I was having the Toyota caps go bad on me every 2-3 years. No more issues again with the stant cap, have had it now for over 5 years! Just no tether like the toyota one, big deal. Just shows ya that even Toyota can be imperfect too!

glad to hear that it's all fixed now!
cheers3.gif
 
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