That is if you were driving at about 60 mph, as outer space starts 62 miles above sea level. To get to the Moon it would take a little longer though, since it's 400,000km (250,000 miles) away - So it would take just under six months of constant driving. Your only real problem (apart from the lack of air for your lungs and for burning the petrol) would be finding a garage to refuel - and also that has a loo!