breathment

I was sitting in my car working on something with it turned off, and i hear this kinda thump sound, and also kinda felt it... like someone came by and kicked my car, i looked around, and saw nothing.... i just thought i was going crazey. BUT today i was working on it, and its a nice cool night and i heard the sound again.. and this time i KNEW it came from my car... It reminded me of when u have a coke bottle or something, and u push it in with the cap in, and the side pops back out and makes a pop sound. So the thought came to be, gas tank. i got out and took off the gas cap, and as always it hissed like crazy, and it THUMPED!!!! i found the source of the thump. i put the cap back on, got under the car to look for the relief valve, WICH I DIDN"T FIND... and i felt the tank, or what i thought was the tank, and it was pretty warm after sitting for half an hour. I resumed what i was doing inside the car and... THUMP again.. i removed the cap again to make sure thats what it was, and it thumped again.. Its pretty loud also.... This is the first time it has thumped when removing the gas cap. 4 times in less then 5 min. scares me. WHAT SHOULD I DO?? im thinking replacing the charcoal filter, and gas cap, and the relieve valve. WHERE IS THE FUEL TANK RELIEF VALVE AT??

should i worry about these sounds and stuff? i don't want anything to explode....

at least i found out what is setting off my alarm..

breathment

top

PimpRod92RS

Get it checked cuz when u have to replace the gastank you also have to remove the rear to get to it Just a thought!

Omega

iTrader: (1)

I wonder if the vent line is plugged. If the gas tank is expanding and contracting due to temperature and the vent line is restriced it might "thump" as the tank pressure changes. There is a valve behind the plastic panel in the drivers side wheelwell. I think that could be your problem or perhaps its the charcoal canister. Have a look, but a shop may be able to diagnose it properly.

breathment

rear wheel well??

Omega

iTrader: (1)

If you are standing at the wheel, look to the right in the upper corner, behind the fender. There is a plastic sheild that covers the fuel fill tube. Next to the tube there is a plastic hose that has a vent/check valve. Check to see if that valve is covered in road grime or is blocked in some way.

TomP

I thought that vent valve was located directly above the brake line, for the rear axle? On the f-bodies I've seen, the plastic vent is on the same bracket as the one holding the end of the rear brake line to the body, right before the rear brake hose. Did this change for later model cars?

Our gas caps are the non-vented type, right?

breathment

ahh. look what i found

its #17.. its pretty much the same for other engines\years..




and yes i think our gas caps are NONvented ones..