There was a man who enjoped his sex life a lot, but sometimes had problems gettin 'it' up, so he went to see his doctor, his doctor said that to help it stay up he needed to masturbate a couple of hours before sex.
The man agreed but couldnt think of any good places, he thought of the toilets but realised he may be heard, his office, but someone may walk in.
As he was driven home he thought of the perfect place, he pulled his car onto the side of the road, got out and layed out underneath the car, pleased with the comfort and discretion he shut his eyes started to masturbate picturing his wife.
After about 10 minutes a police man came and asked him what he was doing, his eyes still closed and masturbating he replied 'erm just checking everythings OK'
'Yeah OK, well while you're down there you might want to check the brakes because your car rolled down the hill 5 minutes ago!'