R. P. wrote:

> "Grumpy AuContraire" <Grumpy@ExtraGrumpyville.com> wrote:
>
>> Be sure that all the remnants of the old leak are removed from the
>> windshield. Also, there are anti fogging agents available in your FLAPS.
>
>
> I took it to a good mechanic who found the heater control valve not
> closing completely and letting hot coolant into the heater core even
> when the valve was set to closed position. I don't know how this could
> effect moisture getting into the air vents but it looks like the
> replaced control valve fixed the problem. Go and figure ...
>
> R. P.


Two main suspects for excessive windshield fogging are:


a) Remnants of anti-freeze from a leak, (previous or otherwise)

b) Remnants of vinyl deterioration from heat/age


Both can drive you nutz...