I had a whirring sound happening after track time last night, found out my AC idler was not...idling, lol. So i pulled the pulley and belt off until I can pick up another...

Revving the car confirming the noise was gone and now I notice a hissing/air escaping/buzzing sound (new sound...to me)...it was definitely coming from under the car.
I chased the sound around thinking exhaust when I narrowed it down to the fuel tank area..

I searched and searched some more, most of the threads are pretty old (2003).
Some threads say the noise is common with the Z and sports cars, others say the dealership/technician replaced their fuel pump right away.

Is there any final word on this noise?

 

The fuel pump sits on top of the tank. A bad pump, on any vehicle, will make a distinctive buzz sound. Once you have heard it it is impossible to forget.

 

Hissing sound coming from the rear tire area if you kneel next to it. If it's random/intermittent, like someone is letting air out of a tire, or if someone is using a spraycan, that's normal. Just the fuel pump doing it's thing.

 

The pumps seem to get louder when the car is pushed a bit. As long as its quiet on cold start it should be fine. The aftermarket pumps are even louder yet.

 

Hmm, the weird thing is, I just started noticing that sound a week ago after a year of owning my Z, definitely normal? No rattling, just the same hissing sound without any specific pattern.

 

This is why I asked because it is def. an odd sound, lol.
My 240 had an aftermarket fuel pump, it is not that kind of sound. The sound is very close to air hissing from a tire. And it is intermittent, as it wasn't doing it this morning.

Thanks for the input fellas.

 

my diagnosis is one snake and six bees.
lol..

k ill leave now.. bye.

 

No snakes or bees this morning, definitely random,
I've chosen to join the side that ignores this sound.