Strong smells from vents when air is on or recycle, strong enough to cause cough

FAR AS THE SMELL,, MIGHT BE MOLD IN THE A/C SYSTEM,, DOES IT HAVE A CABIN AIR FILTER?, MIGHT TRY MIXING SOME BLEACH WITH WATER, USE A SPRAY BOTTLE, WHILE A/C IS ON RECYCLE, AND CAR RUNNING, IN A WELL VENTLATED AREA, WITH DOORS OPEN,, SPRAY A LITTLE BLEACH MIX ON THE PASSENGER SIDE UNDER THE DASH,, ** DON`T WET THE CARPET** YOU WANT THE MIST TO BE PULLED INTO THE A/C ,, THIS USUALY WILL KILL THE MOLD OF ANY IN THE SYSTEM..