How do I clean the ac evaporator? it smells of cigarette smoke.

Sounds like the ac evaporated is leaking. You need to put some dye in the system and check it with a black light. You can purchase a small light for just a few dollars autozone or harbor freight has them.

Use air fresheners to eliminate smoke smell. After cleaning out the car, raid your pantry for odor eliminators. Dryer sheets placed under seats will help freshen the air. Also consider putting an open box of baking soda or a bowl of kitty litter in the car to absorb cigarette smell

How to Get Cigarette Smoke Smell out of Car

If it is smoke you will smell it as if there is burning plastic. Some ac units produce really cold air and what you may be seeing is frosted air from the evaporator coming out the vents. It is an indication that the evaporator is actually icing up and not working efficiently.

I could be that the evaporator core started to freeze up and what you saw was the steam coming off of that.

You need to clean your A/C main vent from center console using a special A/C cleaning equipment with ultrasonic waves. Here in Europe it's easy to find a workshop with this special A/C cleaning equipment with ultrasonic waves. I suggest you to search a workshop in your area, and ask them for this special A/C cleaning equipment with ultrasonic waves.

Your heater core has developed a leak (of coolant). The smell is the "sweet" smell of ethylene glycol,
a component of engine coolant. The white smoke is steam coming from the heated coolant evaporating.
The coolant is dripping into your duct work under the dashboard, and apparently being evaporated
out of the ductwork and sent into the passenger compartment, meaning its a small leak.
When the leak gets worse, you may get wet carpet on the front passenger side.

Hi and welcome to FixYa, I am Kelly. Actually if there is mildew in the system it takes a serious cleaning of the evaporator coil and near by plastic housing / ducting to get rid of the smell. Mildew usually starts forming on the evaporator coil and compartment when the compartment drain gets to be really slow from debris or a dust clog. You can try filters and air fresheners but all they will do is mask the mildew odor. Once the mildew routine starts the only real fix is a serious cleaning of the evaporator coil, compartment and nearby air ducting. Often it takes a good mild and mildew remover to get rid of the problem completely. The evaporator compartment will for sure have to be opened up. If a service shop is going to do the cleaning job correctly they will most likely pump out the freon in the AC system and remove the evaporator coil for proper cleaning. It is not a cheap fix as it is labor intensive and requires the AC system to be drained and re-serviced. Demand that they clean the compartment drain during the cleaning process. My comments are what it really takes to purge the mildew from the AC system correctly. Your call as to fix it or live with it.
Thanks for choosing FixYa,
Kelly

getting rid of cigarette smell is nigh on impossible,without taking down the whole dash/heater matrix/a/c system.and steam cleaning the whole thing.you could try an aerosol spray(from a dealer)that you spray into the outside air vent,but that only maskes it,unless it is very strong.(the nicotine sticks to everything)smoking should be banned in cars......same as cellphones.....

professional cleaning sounds like your best deal unfortunatley with what you are describing it will cost @$400 to $500 to clean. If you decided to quit smoking it might take you about month and a half of your cig money to pay for the cleaning

It might be because recent owners smoked cigarettes in the vehicle. Also, the AC vents may have a little mold which can cause a bad smell until the air flows through.