Hi all at the fiat Forum, We done it and cured it, it turned out to be the alternator peaking at 17volts at tickover, which was causing the cutting out at tickover, i got a secondhand one off e bay for £25.00, its fitted and the car is running fine, although the battery will need replacing as its only holding a charge for a week, i should imagine its the result of boiling the battery with extra volts, i got one off euro carparts for £37.00 deliverd [exide].
now all i will do is sell the replacment seicento, black sport alloy wheels etc..