Heater leakage and heater motor always on

[Game Over]

This evening was rainy. My friend, who seats on the right front seat said that he feels how the water drips on his boots. It’s not an antifreeze it was just a water. Also the heater core is new. Think the water comes by heater air intake below the right wiper. Any solution, guys, to prevent this leakage? I think about a vertical half of 2 liter plastic bottle as a cap above it, I saw this on old Fords with the same problem, by maybe you know a better solution?

The other problem with heater is the always working heater motor. It runs at slow speed even the heater is in Off position. On the other hand it changes its speed only in Hi position. Other speeds are dead. Checked the heater resistor module with multimeter - there is no open circuits. Any thoughts?

 

[81Regal]

This is a very common problem, its ussually one of a few issues.
1: Plugged drain in the bottom of the heater box
2: Dried out seam sealer allowing water to seep in between the heater box and firewall.
3: Dried out sealer around the window/ missing the plastic piece in the corners of the windshield.

 

[Game Over]

This is a very common problem, its ussually one of a few issues.
1: Plugged drain in the bottom of the heater box
2: Dried out seam sealer allowing water to seep in between the heater box and firewall.
3: Dried out sealer around the window/ missing the plastic piece in the corners of the windshield.

What about plastic piece? I have one, which looks like brick with the hole in the middle, but don’t know where is it need to be

 

[81Regal]

The plastic piece looks like a sheet of plastic, about 12 inches x 6 inches that is glued in placed in the lower corners.