My sister in law has a Chrysler Grand Voyager which is nine months out of warranty. For the last year, the car has had to be taken to either the main dealer in Cornwall (35 miles from where she lives) or, at best, a local tyre depot - as every time the tyre valve is connected to a tyre pressure pump the valve snaps and the tyre immediately goes flat.

The tyre low pressure warning alarm will sound soon after new valves are fitted meaning a trip to a tyre specialist ot the main dealer 'Carrs of Cornwall' at Indian Queens. Each repair is costing £100 - £150.

Is this a known problem? Would my sister in law have any recourse with the dealer as this problem manifested itself before the warranty expired without a satisfactory resolution?