hi all, have a problem with my 1995 xjr6 s/charged. for the last few weeks it has been hard to start (hot or cold) but when it did it ran fine. now she wont start at all and can smell petrol after a few goes. have had new coil packs fitted and plugs. on checking the plugs on the weekend they were black and sooty. any ideas please what to check next. thanks.