I have a '94 Mazda B4000 (rebadged Ranger with 4.0 liter engine). For a long time (years!) it has seemed like the air conditioner does not blow as hard as it should. The blower sounds like it's running OK, just not much airflow out of the dash panel outlets.
Today (after putting if off for years!) I finally got in the right mood, and dug into it. I pulled the air cleaner and coolant overflow/washer fluid tank out of the way, and removed the blower, intending to check and see if the blower motor was running properly, and to see if it was getting full voltage when on high speed.
Removing the blower, I saw bits of leaves in the ductwork. I removed the dropping resistor assembly, and it was FULL of leaf bits! The blower is fine, the AC evaporator core was stopped up with leaf bits!
I used a shop vacuum (with the hose at the blower passages) and compressed air (blowing in at the dropping resistor pack opening) in the heater unit housing, and blew/vacuumed out all the leaf bits. Used a piece of rubber hose on the air blower for flexibility, then a piece of plastic tubing pressed into the end of the rubber hose as a blower tip, and was able to flex this nozzle all around to blow out all the leaf bits. Used a flashlight and a 'mirror on a stick' through the blower duct to inspect the entire surface of the evaporator core and make sure it was all clear.
Put 'er back together and now it flows more air on 'low' than it used to flow on 'high'.
Not a big deal, but a nice little evening project with a good result.
That's what I did with my (rebadged) Ranger today!