Just took a look under the bonnet and my induction hose has a big tear in it. Is this common and will this be losing power?
If you mean the big black hose that runs from the airbox to the inlet manifold, with the sort of thick lines running over it, then yes its a comman thing to split.
Not sure about tear mind.
Mine has split and still is, its on my list.
You can get replacement SFS hoses in a variety of colours. These seem to be a comman choice. I'll be getting a black one soon.
So you are basically letting unfiltered, dirty and dusty air directly into your inlet manifold? Surely that can't be a good idea...