How do I fix my irrigation system it always leaves white spots on my car
You can adjust the pressure on each sprinkler by turning a little screw on the top...or park somewhere else.
To fix your irrigation system, you need to check the pressure of every sprinkler of the device and the way its working. You may be required to adjust the levels of the pressures for it not to leave any spots on your car.
You could put a filter on the water for hard water that will stop it
...and there's no controlling the wind that will blow drops onto your car...