Do Car Spoilers Prevent Vehicles from Taking Flight?

[Proko]

According to the Bernoulli's Effect "The pressure in a fluid decreases with increased velocity of the fluid. (The faster the liquid moves, the lesser is the pressure in that liquid.)"
So the air must travel faster across the top of the car, decreasing the pressure, causing the car to have more lift from the less dense air. there is no kind of new upward pressure toward the bottom of the car.
Yes there is upward pressure on the bottom of the car, but it does not increase.