A/C smells like an old ashtray for no apparent reason

[user52165]

Originally Posted by JTK
Sorry if I missed it, but how are you going to get directly at the A/C evap coil on a vehicle without going through the time and money in removing and replacing it?



Go in through the cabin filter or the drain valve. No need to remove it.

Kits come with a special hose.

 

[Fsharp]

Maybe someone flicked their cigarette butt onto your windshield and it rolled down into the air intake.

 

[ZeeOSix]

Originally Posted by cwilliamsws6
Originally Posted by laserred96gt
I had the same issue on my mustang and occasionally on home AC on very humid days and then the smell would go away.

It's not really humid here, it's 90 degrees out though.


Even at 50% RH at 90 deg F there is a lot of water vapor in the air. The A/C evaporator gets very cold and that water vapor freezes on the surface. The longer the A/C is ran, the more water vapor volume freezes onto the evaporator. When you shut the car off everything warms up and the frozen water thaws and is supposed to drain out of the evaporator box onto the ground. If there's excess moisture build-up over time it can start getting moldy and musty smelling.

Check to make sure the water drain isn't clogged for starters.

One trick I use is turn the A/C off about 5~10 min before getting to my destination which will allow the evaporator to thaw quicker and drain and dry out some before parking the car.

 

[AC1DD]

Originally Posted by user52165
Originally Posted by JTK
Sorry if I missed it, but how are you going to get directly at the A/C evap coil on a vehicle without going through the time and money in removing and replacing it?



Go in through the cabin filter or the drain valve. No need to remove it.

Kits come with a special hose.


Yes some cars you can reach the evaporator by way of removing the cabin filter or blower fan.

Like the other guy said you want to make sure you use a AC coil specific product (NOT products with alcohol, ammonia, vinegar, ect.) they can be corrosive to aluminum. Foam coil cleaners are the best because the life dirt away from the coil so the condensation from the coil can be used to flush the dirt and grime off.
That being said if you can reach the coil from the blower fan opening flush the evap gently with tap water and then run the AC for an hour or so to keep tap water mineral deposits from occurring on the coil as well.