Gas smell and hissing

[digitaldragon03]

Yesterday, i was running low on gasoline (1/8 tank) and the car stalled on me a couple times when i was at a stop. The car was also bucking pretty hard. I remembered i accidentaly put 87 octane in the car about 3 weeks ago and hadnt put any gas in since. Thinking the car was going nuts because of the 87, i went and put in half a tank of 91. The problem went away and i continued on. Today, i start the car and i get out to get something from the house. As i get towards the rear of the car, i hear a hissing sound and a gas smell. I get under the car and notice the gas tank is throbbing. I can hear the hissing, but couldnt pinpoint it. The gas tank throbbing is what is scaring me, what do you guys think it is? Just a leak?

[rob101]

sounds like an exhaust leak, hopefully :(

[SRR2]

This sounds like a fuel pump problem. There's an access panel in the trunk where you could at least have a look at the top of the tank. You should refer to the Bentley for further information on this.

[digitaldragon03]

Fuel pump, sounds costly. Im hoping one of the lines is loose. You guys think it could be the fuel filter, i havent changed it and i bought the car a year ago.

[632 Regal]

gas tank is throbbing???

[digitaldragon03]

Yeah, like if you suck on an empty bottle of coke and then release.

[632 Regal]

whip that thing into shape and sell it to me for 3000 and ill take care of it for you.

[digitaldragon03]

The car cost me $8000 a year ago Wendsday. Its going to be a sad anniversary. I got keyed like 2 weeks ago, so it was already in pain. Thrust arms, fuel pump, o2 sensors, paint job, there goes the money i earned over Winter Break.

[632 Regal]

OK Ill go 3500 then. thanks for the maintenence.

[digitaldragon03]

Thanks for the support.

[632 Regal]

seriously we nee much more info before sayin what could be goin on. could be anything, just messin with you.

[Kobe Diesel]

Yeah, like if you suck on an empty bottle of coke and then release.

Check that the tank vent is not fouled or blocked. In my line of work, an unvented tank can potentially collapse - not good.
also sounds like your fuel pump is part of the problem.
I dont think automotive fuel tanks are designed to withstand vacuum conditions, hence the "throbbing".
Correct this before you have a catastrophe on your hands and end up being the next HAZMAT case on your local streets.

[Bill R.]

check valve in the cap that allows air to be sucked in as the fuel is pumped out.. If its bad the tank can collapse inward. I've seen it on a number of electric fuel pump equipped cars. Remove the gas cap and see if you still hear the throbbing /hissing.




Check that the tank vent is not fouled or blocked. In my line of work, an unvented tank can potentially collapse - not good.
also sounds like your fuel pump is part of the problem.
I dont think automotive fuel tanks are designed to withstand vacuum conditions, hence the "throbbing".
Correct this before you have a catastrophe on your hands and end up being the next HAZMAT case on your local streets.

[Alexlind123]

Looking at it from a logical point of view, air needs to come into the tank from outside to replace the gasoline coming out. If air cant get into the tank, the tank will compress tto try to maintain the same pressure. So, logically an air passage must be blocked (or partially blicked considering the hissing.

Sorry i cant help you any more.

[632 Regal]

inspect the gas cap