Whirring sound - a bit like a buzzer?

[neilz]

When my car is idling, there is a loud whirring/humming sound almost like a hazard buzzer half way along the car (or so) on the driver's side. The car drives fine (fuel consumption is getting dire so taking it in for that Halfords 'Fuel Service Plus' soon (worked wonders on my old 124)) but that sound is just getting very annoying. What could be causing it? The fuel pump?

 

[BlackC55]

I suspect the fuel filter is blocked or the fuel pump is on it's way out.

 

[neilz]

Thought so, thanks. Would that explain surging fuel consumption?

 

[neilz]

The sound is very loud and very distinctive by the way, cuts through the engine sound (all you can hear is that when the car idles, it's almost as if the car's silent otherwise)

Edit: The car usually takes two attempts to start, could this also be related?

 

[neilz]

Bump (sorry!)