pplaut

If I raise the body all the way up, turn off the car, come out to the car the next morning the body is still raised. If I drive a car less than 45 mph the car remains raise and drives as expected with the body high. Lowering the body to the normal height and driving at any speed eventually the front end sags. Sometimes, if I parked the car in the body is not raised there is a hissing from each air shock. I would say the air shocks have a problem, other than as long as the car is in up with mode and under 45 miles per hour I can drive with no hissing noise and no leaks whatsoever.
This seems like a sensor to me, but I have absolutely no idea what sensor to look at.
I appreciate any help anyone might be able to provide.
Thanks!
P.