gas cap question

[GreddySpyder]

I went to advance auto to buy a new gas cap today and they had two types, pre-vented caps and normal caps, they didn't know the difference, neither did i? Anybody know the difference?

 

[InFlames]

Hmmm.. Good question, I don't know but I would say go with the normal one

 

[Black95GSX]

Hmmm... that is the #1 sign that the place you are going to doesn't use the correct resources to lookup the appropriate parts for any given car.


If your gas cap is dead, I'd suggest going to the dealership to get one.

I can't remember how many non-oem gas caps I've seen fall apart.

 

[insane147]

i believe one is vented so you dont get a pressure build up in the tank (for carbed cars so as not to flood the bowls mostly) and non-vented which i think dsms use as mine always blows air out when opened.

 

[GreddySpyder]

I don't know what is going on. I replaced the gas cap since i never hear the "hiss" of fuel pressure escaping whenever i take off the cap. I put the new cap on as soon as i got out of Advance Auto, and when I got home I unscrewed the cap, but I still didn't hear a hiss. Any thoughts?

 

[Black95GSX]

You might have a leak....

I know we use a "smoke" machine in our shop which fills the lines with a nice thick smoke, so you can see where it's coming out..... other then that though, I don't know what you could do to find your leak.

 

[SD GST]

So is it going to hurt anything if you don't hear the "Hiss" sound when you remove your gas cap? I have never heard the "Hissing" sound on my car. I bought it at 75,000 miles and have had it for 15,000...

 

[insane147]

i wouldnt worry about the hiss sound, that is what the evaporator canistor is for, to purge those vapors and pressure from the system, i think?

 

[EclipseTrbo420A]

Hmmm... that is the #1 sign that the place you are going to doesn't use the correct resources to lookup the appropriate parts for any given car.


If your gas cap is dead, I'd suggest going to the dealership to get one.

I can't remember how many non-oem gas caps I've seen fall apart.

I know this is like the first thread ever made on tuners, but atleast im searching...

Anyway..how the hell does a gas cap DIE? I have this stupid CEL but I get the HISS and eveything anythoughts from some newcommers?

 

[Defiant]

The seals eventually fail, or the venting mechanism gets grit into it and causes it to throw a CEL.
It can be one of the most difficult CELs to cure, if you don't think of checking the cap.

 

[EclipseTrbo420A]

It all started when I removed DSMLink and put in a 96 GST ecu, it was all fine accept for the minor CAS problem between the 2ga and 2gb. So I got a 98 GSX ecu and put that in...10 minutes later Gas Cap light, been on since. Thanks for the help. Ill try a new cap first, it cant hurt.

 

[azkkr]

Pre-Vent represents the latest in fuel cap technology and is designed to permit the controlled release of fuel tank pressure from volatile fuels. While removing the cap to refuel, a 1/2 turn of the Pre-Vent cap releases the fuel tank pressure into the atmosphere before the cap's sealing gasket is released from the filler neck. This feature dramatically reduces the possibility of fuel expulsion from the filler neck when the cap is removed.

Did changing the cap for an opm new one fix the problem?