Hi, I have a 1998 328is with about 138000 miles on it. When my a/c is on, it cycles on and off every 30 seconds or so (which is correct based on the temp), but when it cycles on, it makes a 'whirring' noise until it cycles off, then when it goes on again, it starts whirring again. Does anyone know what this could be and how to fix it? Thanks a lot for any help.
