Three weeks ago I purchased a 2002 78,000 mile Porsche Boxster 3.2 S from an independent dealer, after first having had the car inspected by Peter Morgan Ltd. Now one of the Lambda sensors has failed and the Porsche specialist recommends replacing all four at a cost of £622. I paid the full asking price and was assured that it has a three-month dealer warranty. The dealer is now saying that the warranty does not cover these items. I realise that an older vehicle such as this that will involve increased running costs, but to be faced with a bill of this magnitude so soon after purchase is a little hard to stomach. I am unsure what my legal position is, have I just been unlucky?