I noticed that an oily substance has been splattered about way up front under the bumper cover on the drivers side of my 96 SL2. It dripped a little bit from the black plastic piece that is just behind the air deflector with the springs. I'm thinking it may have been from the AC. Is there any way (short of having it tested) to tell if it is low? Also, If it has leaked, is there any harm in leaving it until spring to be fixed? Andy