when I start my z first thing in the morning there is a grating type noise from under the bonnet, this increases and decreases when you turn the wheel, which incedentaly seems 'jerky', it runs like this for about a minute then is fine for the rest of the day, any ideas anyone? :confused:

Check your PS fluid.

Should be a nice ruby red, any darkening might mean its contaminated or the rack is worn (or the pump is)

Best thing is to replace fluid..

Flush it out and replace it.

when I start my z first thing in the morning there is a grating type noise from under the bonnet, this increases and decreases when you turn the wheel, which incedentaly seems 'jerky', it runs like this for about a minute then is fine for the rest of the day, any ideas anyone? :confused:

yeah but would any of that mean that the problem would stop after about a min?