Manta/ Ascona heater question

[oldopelguy]

So, in an effoert to truely asses the ammount of battery acid damage to my fire wall I removed the heater and dash insulation to take a good look. With the heater out I noticed for the first time a blanking plate in the firewall below the vent inlets but above hole for the heater and defroster, in the vertical part of the firewall. It doesn't have any screws or anything in it, but before my curiosity forces me to pry it out I thought I should ask if anyone knows where it goes or what's behind it. Thanks in advance.

[Gary]

- A/C? {{guess}}

[ddoyle]

Stephen, it has been a long time since I had my heater box apart, but I rember the plate. I beleive it helps to seal part of the air distribution housing, the back of it(firewall side) is open. The metal plate was just glued to the firewall. Mine had come loose and made a very annoying rattle when the blower was on. I just removed it, the ductwork still seals well to the firewall, I am sure there is some air leakage, but I did not notice any difference in airflow, but it is quiet now. Hope that helps.
DAN

[oldopelguy]

Thanks Dan, you're the man. Just the info I was looking for. I'm actually planning on building a completely new heater assembly for the car, so I may end up either using the hole or covering it more permanantly.