hi guys, was turning my 1.4 mk3 golfover today when I turned the airconon all the way to '4' and the revssuddenly dropped by like 100/200 revs. Never noticed this before, but seeing as ive never turned the air cononlike this while sat still idling i wouldn't. Just wondering what it might be, thecar runs fineandit doesnt seem tobe a problem,just curious what itmaybe. Like imentioned, it drops the revs but then raises straight back to the revs it was doing before the air conwas turned on. I thought it mite hav bin thefact the air con was on as hot as it could go and seein as it had only just gotten to normal temperature (the engine), it was a bit of a struggle or sumthing but then turned the air conoff and turnedit straight back to4 on full cold andit did the same.

Any ideas?