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gas cap changing performance?

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Old Jan 18, 2012 | 07:29 PM
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gas cap changing performance?

on a hunch ,i know that our cars use a ccp system (carbon canistor). Ok, well i tried a vented gas cap tonight and noticed that the car acceklerated a little smoother but felt less torquey. I then put back my locking gas cap and immediately felt myself being pushed back in my seat with the torque i am familiar with. Strange. Anyone else exp. this? For the record, when i took off the vented cap i had no pressure release like i do with my regular cap. Maybe that pressure is good.
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Old Jan 19, 2012 | 08:30 AM
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Re: gas cap changing performance?

Anyone??
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Old Jan 19, 2012 | 08:31 AM
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Re: gas cap changing performance?

No one experiences high pressure when they remove their gas cap? Havent any of you tried a vented cap because of this? any results?
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Old Jan 19, 2012 | 09:58 AM
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Re: gas cap changing performance?

guess not, i actually never heard of these, how much is the average cost so i can try one? my cap is pretty old and about itme for a new one.
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Old Jan 19, 2012 | 10:10 AM
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Re: gas cap changing performance?

Originally Posted by GreenCamaro13
guess not, i actually never heard of these, how much is the average cost so i can try one? my cap is pretty old and about itme for a new one.
I bought my locking gas cap at Walmart, its a Stant. I got the factory cap and drilled two small holes in it for testing purposes.
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Old Jan 19, 2012 | 11:42 AM
  #6  
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Re: gas cap changing performance?

aaww i see, yea. whitch would you reccommend for me? i like speed and lots of it,
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Old Jan 19, 2012 | 01:23 PM
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Re: gas cap changing performance?

lol, its a stant locking cap,it was like $8
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Old Jan 19, 2012 | 01:56 PM
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Re: gas cap changing performance?

Check the gas tank vent. It's on a piece of hose & hangs from the hose.

There is a discussion on it, but I don't recall the thread title, or exact location.

Seems easy to get to IIRC.
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Old Jan 19, 2012 | 06:47 PM
  #9  
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Car: 1989 camaro rs convertable
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Re: gas cap changing performance?

Originally Posted by t-top havoc
Check the gas tank vent. It's on a piece of hose & hangs from the hose.

There is a discussion on it, but I don't recall the thread title, or exact location.

Seems easy to get to IIRC.
doesn't the gas tank vent into the charcoal canaster under the hood?i know its supposed to be under a vacumn to keep the gas fumes from leaking into the air.
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Old Jan 19, 2012 | 07:22 PM
  #10  
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Re: gas cap changing performance?

Originally Posted by zenish
doesn't the gas tank vent into the charcoal canaster under the hood?i know its supposed to be under a vacumn to keep the gas fumes from leaking into the air.
Fumes go to canister and are stored there.
Are purged to the engine under programmed conditions

Originally Posted by ninetyone
No one experiences high pressure when they remove their gas cap?
Havent any of you tried a vented cap because of this? any results?
If line to canister is blocked or system not being purged then common to get pressure build up in tank as noted
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Old Jan 19, 2012 | 07:27 PM
  #11  
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Axle/Gears: 3:42
Re: gas cap changing performance?

yes,but someone else told me its normal to get pressure
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Old Jan 19, 2012 | 07:28 PM
  #12  
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Transmission: 700r4
Axle/Gears: 3:42
Re: gas cap changing performance?

i was curious on how a vented cap would change performance and i did feel a difference. yes, i had no pressure when i went to remove gas cap,but car performed differently,just didnt feel as powerful
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Old Jan 19, 2012 | 07:29 PM
  #13  
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Transmission: 700r4
Axle/Gears: 3:42
Re: gas cap changing performance?

i want to learn why?
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Old Jan 20, 2012 | 08:59 PM
  #14  
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Re: gas cap changing performance?

Try an actual vented cap, not a reg cap with holes in it.

I'm about to order mine from mdm it's like 10 bux

My pressure is gone in the tank after I fixed my tank pressure valve
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