cars not starting?

[RosscoMann]

my m8s saxo isnt startin he trys turning the key for a while but sumtyms it starts and other tyms its dead? it also revs up by itself:O any1 have any ideas? thanks.

[Azza-VTR]

Does it start up then die straight away?
If so it is most probably the IACV - cost £37 brand new from Citroen and will be the exact one you would want
Has your mate checked his coolent and oil - could be a sign of Head Gasket Failure if the above is not the case however with it self reving aswell I would definately say the IACV (Idle Air Control Valve) :y: