Air ride pump in car will kick on randomly even if the car is off on 1990 Oldsmobile 98

The air pump for the rear air shocks on my 90 Olds 98 will randomly turn on whether or not the car is on. I can't hear any vacuum leaks in the line, so what could it be?

They will do that from time to time, you haven't owned this car very long... have you...?