Accessing A/C coils

[MixEngineer]

Anyone know the locale for the A/C evaporator coils? I assume it's behind the firewall on the passenger side. Is there a "quick" way to get to these to clean them?

Thanks so much.

[jimmy57]

On XC90, or any P2, P1, P3 the evaporator is in the center of the system. There is no easy way to get to them to clean but you could cut a slot and fashion a very slender water nozzle. The best way to know evaporator location is to find the evap temp probe above and to the right of the accel pedal assy. on the white case. There is a temp sensor on a stalk that is placed to be 1/4 inch behind the evaporator for accurate sensing purposes. the evaporator is about 3 inches thick but drill small test holes (shallow, very shallow) and probe to define the evaporator location before cutting a section out for access to be glued back later (or use the REAL aluminum duct tape to cover your opening).
I use a 1 gallon garden sprayer and mod the wand (shorten it) so I can manipulate in tight quarters to spray the evaporator. The stuff will run out of drain but be sure to clean the drain hose when you are done and after you run the car with a/c on for a while.

That vehicle has 100% filtration passing the evap from the cabin filter. It shouldn't be dirty. I have not seen one with airflow problems due to dirty evaporator. What leads you to believe it is plugged?

[MixEngineer]

Jimmy, thanks.

It smells faintly of mildew, even after replacing the in-cabin activated charcoal/carbon filter. I would assume the only place of condensation within the unit (hence the potential for mildew growth) would be the coils.