Passenger floor noise, revisited

[Padawan]

I posted a while ago about a noise that my '08 Cabrio makes whenever it's running. The noise is most noticeable when the engine is idling and the climate control is switched off. With my head near the passenger side floorboard/footwell, there is a distinct "whooshing" sound, almost as if liquid or air is flowing through something. It is continuous, and doesn't seem to change sound or pitch if the engine speed is increased.

Does anyone have a similar noise, or any ideas as to what this might be? If it were warmer, I'd be out there doing more poking around, but I though perhaps someone might have an answer as to what components are in that particular area and might be generating the noise.

Is the fuel pump there? Where are the coolant lines that run to the radiator? How about the fuel lines?

I am certain it's NOT the A/C or heater fan, nor is it coming from the engine compartment behind the seats.

[Smartfor2guy]

The fuel tank is right behind the passenger seat so its possible if might be the fuel system

[dbwill]

How about the front radiator and rear engine, coolant

[Padawan]

Originally Posted by dbwill

How about the front radiator and rear engine, coolant

I was thinking it might be a coolant hose, but I've never seen a diagram of where all the hoses run from front to back.

This noise is coming from a very particular location.

[smartSEATTLE]

Originally Posted by Padawan

I posted a while ago about a noise that my '08 Cabrio makes whenever it's running. The noise is most noticeable when the engine is idling and the climate control is switched off. With my head near the passenger side floorboard/footwell, there is a distinct "whooshing" sound, almost as if liquid or air is flowing through something. It is continuous, and doesn't seem to change sound or pitch if the engine speed is increased.

Does anyone have a similar noise, or any ideas as to what this might be? If it were warmer, I'd be out there doing more poking around, but I though perhaps someone might have an answer as to what components are in that particular area and might be generating the noise.

Is the fuel pump there? Where are the coolant lines that run to the radiator? How about the fuel lines?

I am certain it's NOT the A/C or heater fan, nor is it coming from the engine compartment behind the seats.

Have your dealership check your fuel pump. The pump is located directly below your passenger seat. I have replaced 2 of them here at our shop for just this reason.

[Padawan]

Originally Posted by smartSEATTLE

Have your dealership check your fuel pump. The pump is located directly below your passenger seat. I have replaced 2 of them here at our shop for just this reason.

Can you elaborate a bit about how they might go about "checking" it or how you determined that the two you replaced were faulty? I would hate to go through the trouble of bringing it in and arranging alternate transportation only to have them tell me it "seems normal". Perhaps if I know how better to explain the problem, they will be more effective at fixing it.

[smartSEATTLE]

Originally Posted by Padawan

Can you elaborate a bit about how they might go about "checking" it or how you determined that the two you replaced were faulty? I would hate to go through the trouble of bringing it in and arranging alternate transportation only to have them tell me it "seems normal". Perhaps if I know how better to explain the problem, they will be more effective at fixing it.

When we first heard the noise it sounds like a hissing. Noise is louder from the interior of the vehicle by the passenger foot area.

Raise the vehicle and remove the splash guards, the noise is very loud from under the vehicle with the guards off. Very apparent if it is the fuel pump that it is coming from the tank.

[Padawan]

Thanks. Was there some sort of updated pump to solve this problem, or is it simply that some are noisier than others?

[kwajman]

I'm new so take it for what it is. I was at the Milwaukee dealer a couple of days ago and they had a 'blown up' cell of the car. Meaning they had a stripped down version, no panels, no anything except the 'cage' of the passenger area. Where the battery sits is under the passengers feet in a little well. Under the battery is a BIG hole that could cause a whooshing/hissing sound if air is passing over/through it. Kind of like blowing over a bottle can cause a whistling sound. Could this maybe be your answer?

[Padawan]

Originally Posted by kwajman

I'm new so take it for what it is. I was at the Milwaukee dealer a couple of days ago and they had a 'blown up' cell of the car. Meaning they had a stripped down version, no panels, no anything except the 'cage' of the passenger area. Where the battery sits is under the passengers feet in a little well. Under the battery is a BIG hole that could cause a whooshing/hissing sound if air is passing over/through it. Kind of like blowing over a bottle can cause a whistling sound. Could this maybe be your answer?

Unfortunately not, because it is constant whenever the car is running, even when parked. I'm thinking it must be the fuel pump, but wondering how much noise is "normal" and if I should bring it in to the dealer.