This one's a little tricky; it's sort of like a carseat glory hole. The man kneels on the front seats facing the back seat of the car, straddling the gear shift and parking brake. He sticks his erect cock through the space between the seats. The woman sits in the back seat and blows him. If there's enough clearance between the seats, she can try backing her ass up to the gap so he can fuck her doggy style.