Engine humming and vibrations in the pedels

Hey guys,

I'm having some problems with my 03 Fabia TDI with 20k on the clock. While I'm waiting for my local dealer to get back to me, I thought I'd see whether anyone has had any similar problems.

Symptoms are a droning humming noise coming from the engine bay (could be ok, maybe just the fan coming on) but the main problem is when there is this noise, there is also a varying degree of vibrations through the pedels. Another side effect is that it seems like there is a little less power in the engine.

The vibrations can be pretty bad, and sometimes driving in London traffic is very irritating. All of the pedels vibrate, and because the brake pedel is vibrating too, it feels like mush - almost as if there is an air bubble inside or something.

And then, it can all go away as quicky as it came. Its quite intermittant.

I'm certain it is temperature dependant. On a hot day, it can happen straight away or in a few minutes. It pretty much happens everyday on the way home (when the sun has been shining on the car) and doesn't happen at all in the mornings if I leave early and its cool outside. Stop-Start traffic up a hill and it will happen. Coast down the other side and it will be fine again. If I take the car out of gear when stationary, the pedels still vibrate and the car sounds loud.

Anyone have any ideas?