I'm not a mechanic or a mitsubishi tech at all. I was just going along with a noise coming from the gas tank area and it being hot. There isnt too much in the rear of a car that is going to make a noise when in park and at idle. I just happen to find the info on the relief valve. Seemed to go hand and hand.

 

It could be that, but that would indicate a problem. I say, if the noise wasn't there before, and it makes it consistantly, take it in and get it looked at.

 

Thanks for all the input guys, I will take it to the dealer when ever I get a chance. I'm not sure if the noise was there before or not, its verry faint and could only be heard if your ear is about a foot from the tank.

 

you may be hearing many things. Are you sure its from the fuel tank? If so, obviously the pump will make noise, as will the regulator (located on the pump).
You may hear the "click" of a solenoid from the EVAP system, but its not likely to be heard, nor will it come on often.
There are many things that could potentially be cycling from the rear of the car... I doubt very much you have anything to worry about.

 

You bring peace of mind with you brews, I apreciate your input. I'm 99.9% sure its the pump now, I told the wife to gradually step on the gas, the more she did the more constant the buzz was, so this proves its the pump, since when on iddle it sounds like its going on and off rapidlly. The noise is not intorelable by any means, but can be hear if you have veery attuned ears, I just wanted the peace of mind of knowing it is something normal.

thank you.

 

totally normal, as the pressure regulator is part of the pump.