VR6 Fuel Smell

Hi, when starting first thing in morning, very strong smell of petrol for about 5 to 10 minutes. Then no problem all day no matter how long car has been sitting?
Can see no leak anywhere, but have to keep windows up otherwise it just stinks.
Anyone had this problem that can point me in the right direction.
Cheers
1994 VR6 95,000kms