Unusual Noise 997.1 Any thoughts?

[Beepsquad]

Hi

At exactly 3000RPM in 1st, 2nd and 3rd passing through that point by accelerating or slowing down on the gear I can hear a very high pitched, whirling from the engine/rear of the car. It's only at 3000RPM and lasts less about 1/2 seconds if slowing down and obviously passes through the noise when accelerating almost instantly. The only thing I have done to the engine is to removed the Porsche Sports Exhaust connection to disable the baffles closing. Can anyone think what this might be? You can only hear it with the windows down

Thanks

[Ian_UK1]

Beepsquad said:

Hi

At exactly 3000RPM in 1st, 2nd and 3rd passing through that point by accelerating or slowing down on the gear I can hear a very high pitched, whirling from the engine/rear of the car. It's only at 3000RPM and lasts less about 1/2 seconds if slowing down and obviously passes through the noise when accelerating almost instantly. The only thing I have done to the engine is to removed the Porsche Sports Exhaust connection to disable the baffles closing. Can anyone think what this might be? You can only hear it with the windows down

Thanks

Alternator pulley and/or bearings. The alternators on 997S.1 can be fully reconditioned (new bearings / diode pack / brushes / pulley) for about £100. No need to buy a billion pound new one from Porsche. Removal/reinstallation is about an hour at a specialist.

[Beepsquad]

Phew - Thanks Ian, doesn't sound too painful. Will drop it into the local guys here at GT One in Cherstey, wouldn't take my car to anyone else.

Best

James