[DFBonnett]

It's not an AC leak. The drain for the condenser has clogged and what should be draining onto the road is filling up the plenum and running into the cabin. Look on the firewall on the passenger side about half way down. You should see a piece of rubber hose sticking out of the firewall and pointing down. It's plugged. Rod it out with a piece of coathanger or similar. You may need to get under the car to do this.