you need to replace your heater core.
Most likely your heater core has gone bad.
how do you get to it
heater core is shot...
To replace most heater cores you have to remove the dash on the passenger side.
Should be at the passenger's side firewall
Sound like your heater core is leaking? I have heard about this problem from other achieva owners. I think others have figured out it is a leak from the door moulding which allows water in and it puddles in the floorboard. I don't think it would be from the heater core.
Yes, but you will have no heat. Your heater core is leaking and needs replacing.
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no
The heater hoses.
I had this problem once with a different vehicle. You may check the heater control. That may be the problem. Hope this helps.
Leak in heater core.