Hi people, I have a 2.2 Astra Sri, started driving my car this morning, the power steering felt heavier than usual, thought it may be a flat tyre or low fluid, got to work all tyres ok and fluid at maximum, lifted the bonnet and silence until you move the steering wheel, then some whinning coming from the right had side of the engine bay, definately nothing I've heard before, you can also hear it whilst sat in the car, also the lights dim slightly when moving the steering, but its always done that, any ideas?