Weird buzzing/ rattling noise.

[Alun]

I have a rather strange problem. When I acclerate hard, I get a sort of buzzing/rattling noise which sounds like its coming from the passenger footwell. The harder I acclerate the louder it gets. On a steady throttle there is no noise. It does not change in pitch, just volume.
I have also started to use a bit more fuel than I used to.

Any clues?

[kitesurf_phil]

Isn't the fuel pump on the n/s bulkhead just above the footwell?

I wouldn't be too alarmed though. I spent ages trying to trace a noise that I thought was a gearbox/transfer case problem. I had dropped a couple of blown fuses and they were in the crease of the gear shift gaiter. It took me two days to suss that one. It realy sounded like it was mechanical and only happened at certain revs.

[Guest]

Possibly the air filter rattling in it's casing.

Cheers

[Gizmo]

I know occassionaly that the clip for the sensor [inserted into the pipe from the filter] comes out of the bulkhead

[Alun]

Thanks for the suggestions, will look into them. Have been paying particularly close attention to the noise lately, It starts at 2500 rpm and gets louder as the revs increase. As soon as you close throttle, noise goes.