A.C. compressor is enguaging when in the "OFF" position

I own a 1987 5.0 iroc camaro.The problem is that the compressor is enguaging and disenguaging when the air conditioner is in the "OFF"
position. Does vaccum control the operation of the compressor or could it be the compressor relay??? The a.c. works fine in the "ON" position. Any one who knows about this or had this happen some help would be appreciated....HELP!!!!! I dont want to get robbed by a repair shop and deal with people who lie.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.