acrid smell

Hi all, new member here and new to the sprinter world, I just picked up a 2012 with 43,000 actual miles, runs/ drives great. I am noticing white smoke on occasion, I have noticed it does it every morning which I have ruled out as mostly steam but on occassion I see it after the temperture and...

My 2004 C270 Avangarde Estate has developed an acrid smell which I have traced to the aircon unit. Usually the unit is permanently switched 'on' (I have had the car from new) but I have discovered that the acrid smell stops when the a/c is switched off. Is this likely to be a gassing problem...