Musty odor coming from AC vents the last 2 days. Is there a filter some where that needs to be changed?

Clean vent passages with febreez or something similar by cleaning out cowl beneath vents in front of windscreen (requires some disassembly) and any other vent areas you can get to. Later models have a cabin air filter which can be replaced, but not sure if yours does. Ask at parts store.

The first thing most people should do is get their manual out and find out the location of the "cabin air filter". On many cars, it is behind the glove box. This is a filter that needs changed out from time to time. If you can't find it, drive to an auto shop, ask them to sell you the filter and explain to you how to find it and change it out.
Another thing that can be done for car odor is to clean the leaves off the outside vents near base of windshield, turn on AC, select fresh air (NOT recirculate) set fan at full blast, roll down windows, and spray the outside vents on both sides with Lysol. Scotty Kilmer has a great video on YouTube showing how this is done. "Getting Rid of Stinky Car AC Odors" .https://www.youtube.com/watch?v=VrVc_FXrbHY

A very common malidy, more then likely you have a mouse for a guest in your cabin air filter. Puzzled me for days when my wife's car was turned into a mouse Bed & Breakfast..make sure you change the filter after cleaning the mess out


Thanks Terry

The musty odor is moisture in the HVAC box. Someone needs to check and see if the system is full of freon, then check the circuit going to the ac clutch for power.

the musty smell is from the dampness in your heater I would get it checked at a good Rad shop

It sounds to me if you are having a "musty smell" then you might have a problem with your condensation drain line for you a/c system or a small leak on your heater core. If it is plugged then water will collect in the vent system causing a musty smell from the water not draining and if there is a small leak on the heater core then coolant can collect in the vent system. I would run the a/c on a warm day and look for water draining from the vehicle around where the dash is located to check the drain line. As far as your air cabin filter most are located behind the glove box. You usually need to remove the glove box to get to the filter.

There is no filter for the AC or heater in the 93 Accord. Air for the AC either recirculates from the passenger compartment or is drawn in through the vents below the wipers outside the car. You might try spraying something nice-smelling into those vents to see if it is drawn into the car while the AC is running, set to outside air.
Hope this is helpful.

The drain should go through on the passenger side under the dash....you might need to replace your cabin air filter.

If you run your Air cond on recirculate always try using an air sanitizer in your return vent. Or switch your A/C to outside air flow for for half an hour and raise the rear of your sunroof panel to vent the stale air do this till the smell dissipates and then close he sunroof and reset the A/C to recirculate if desired.

Mold and mildew builds up in the system from moisture in the air, dealers have chemicals they spray inside the ducting to kill these molds and mildews, the service runs about $100, there is no permanent fix, this will need to be done from time to time as req'ed, a short term fix is to spray Lysol into the heating/AC air inlet at the base of the windshield, run the blower on high and set to outside air, spray in about 1/2 can and then turn of the system and let it set.