Ok, so ive got a very confusing problem. So first off, I have a 2000 integra ls 4dr sedan (if thats even relevant to my problem) A couple weeks ago I was sitting in the car, power was off, keys were not in the ignition, in fact it had all been off for at least half an hour. Anyways, i suddenly start to hear this loud obnoxious whining, which sure sounded like a bad fuel pump to me, but I know nothing really. Anyways, I traced the noise to the back of the car, sure sounded like its either coming from the fuel tank, or under my back seat (where the pump is located, correct?) So I start the car up, let it run for a bit hoping maybe thatll make it stop, but nope. I shut the car off, take the key back out, sure enough its still doing it. I decided to leave it alone for the night and see what it did the next morning. So next morning I go out, sit in the car, listen for the noise, nothing. Noise is gone. I try to start my car, wont start. My fuel either evaporated, or completely drained over night. (90% sure my fuel tank isnt cracked) sooooo, I get some more gas in it after a day, the noise immediately starts back up, by the way, it usually just makes the sound when someone shakes the car ive noticed. So anyways, this time, with my lack of knowledge, Im thoroughly convinced its the fuel pump, faulty wiring or something causing it to drain power from the battery. Just a guess of course. So I disconnect the battery thinking thr pump cant be powered if theres no battery, and guess what? The noise is still there! With the battery completely disconnected! So then im thinking maybe the alternator has back up power in it or something, O dont know, im at a complete loss on this. So I call my buddy, explain it all to him, and he says its not my pump, its the pressure in my tank amd to take off the fuel cap... so I take it off, leave it off, and thr noise is gone.

ok, theres my story. Can anybody explain to me what the hell is going on here? And what can I do to fix this issue and be able to have a gas cap on? Thanks in advance for the help!

 

Best Solution: Get rid of this car and find another one.

Also, how can you say you're 90% sure your fuel tank isn't cracked? You decided not to inspect 10% of the tank when checking it out or what?

 

Yeah my 2000 Integra gs coupe will make a whining noise from time to time while its just sitting in the garage doing nothing. I want to say that it has nothing to do with starting or losing gas as it doesnt seem to be effecting my performance or fuel consumption what so ever. I think it may have to do with the Evap / charcoal canister system and pressure is just working its way out. Maybe there are some leaky check valves, I am not that worried about it.

I lol'd at the back up power in the alternator, no that isnt a thing....