comming back from work other day i noticed steam comming out from under the bonnet. I made it to a near by garage and lifted the bonnet. Noticed a weird hissing noise from the intercooler pipe which stopped as soon as it started. waited for all to cool down and opened the water tank cap. Nothing in there...no water nothing. filled up with cold water...about a litre or so and drove home no problems...obviously took it easy. Will book it in to a garage on monday.