small air ride question.. i think??

[devilchild]

yesterday i drove my mark to my work to let the battery charge since its been sitting a week or two... an hour after i shut the car off and hooked up the charger i returned to check the status and heard my compressor kick on.. i didnt notice anything right away ...but upon further inspection i saw that my rear went up about 2 - 3 inches to an ungodly height ( similar to when i hit the ray switch and the front goes down and the rear raises at first ) making my car look like the rear is jacked up like drag cars of old..
why??
should the compressor come on when the car is off??.. or an hour later??..
is this doing this all night??.. and why did the rear go up sooooo frigg'n high??

 

[chicken]

the comp will still run for an hour after the key is off, but as for it going up???

 

[67Continental]

check to see if the height sensor in the rear hasnt fallen off. happened to me in the front.

 

[MarkVIII93]

The whole system should lose power around 20 minutes after the key is taken out of the ignition.

 

[devilchild]

The whole system should lose power around 20 minutes after the key is taken out of the ignition.

so what would make the compressor kick on an hour later??..and raise the car above normal ride height??..