My ac don't blow cold air only hot air and smog got deleted

Hello, That is sort of a confusing statement. The only connection I can draw is that possibly your readiness monitors for a smog test are not ready, but that would not cause the air conditioner to work any differently. If the air conditioner is not working properly, the engine control module may cause this, but I would doubt this protocol would have been included on the software of a 1999 mustang. I recommend bringing the vehicle to a certified shop for a true and honest diagnosis. Here is a link for shops in your area that we have certified for this purpose: https://repairpal.com/ford-within-10-miles-of-rupert-idaho-83350