My daughter's 2000 Accord has and has had a pumping sound. It does it, I guess, almost all the time. When I have noticed it, it will "pump" for a couple of seconds then quit. A few minutes later it "pumps" again. I always thought it was normal and I still don't know that it is not. A few years ago I found 2 of my daughters listening to try and locate it. Then I joined in to try and locate it. We ended up thinking that it was under the back seat, maybe.

Any ideas as to what it is? Should I worry?

 

Sounds like it might be the ABS normalizing the pressure?

 

Probably the fuel pump. The fuel pump turns on for about 3 seconds when you turn the key to build pressure before you start the car. It's located in the trunk, near the back seat. I wouldn't worry.

 

no, actually its located directly under the passenger seat. its normal, all cars have it, its just some are more noticable than others.

 

Fuel pump is inside the tank, and runs constantly with a buzzing sound. The 2-seconds-then-off business is only when you turn the key to ON but don't immediately start the car.

The pumping is probably the EVAP canister. It's located directly under the left-rear seat. (Gas tank is further aft.) There's a couple valves associated with that system & they cycle to purge fuel from the charcoal canister.

 

The pumping that I spoke of is with no key, just the car in the driveway.

 

That's stillthe EVAP canister. It'sletting off pressure from inside the fuel tank.

 

EVAP canister x2. It's the only thing that makes sense.

 

Unless your car has some sort of auto-leveling system installed it's probably the evap as stated. Does the sound come from the engine bay or rear of the car?

 

so, explain what you are doing to make the noise happen. are you bouncing the car? do you just walk up to in and all the sudden...thump. thump. heh..heheh...that's funny. anyway, is it only have a drive? it occurs seconds or minutes after a drive then you get out?

my family once drove all the way to the forest preserve listening to an odd noise from under the rear of the car. turns out the cat hopped up there and was making hella noise on the drive...
[8D]


fyi, year does not do key off evap testing like newer models. so any noise that occurs say...5 mintues or so after shutting off the car is not evap testing. (5 minutes is a stretch anyway)