99 4-Runner Window's Fogging?

[Icemanmn]

99 Toyota 4Runner Problem?
The front of 4 runner fogs up. Blower is working great. When I switch to floor heat/Defroster it gets worse? Is there a control or heater box adjustment?
I replaced thermostat. Heater works, but seems to blow more heat to back of 4 runner then the front?
Thanks.

 

[Derek G]

Are you getting air out of the defrost vents? is it hot?

If you're not getting air it could be a vaccuum line that opens and closes the baffles in the system.

If you are getting air and it is not hot you could have a bad heater core.

If you're getting hot air you could have moisture in the system or in the truck (check for dampness under floor mats) or you might not be waiting long enough for the windshield to heat through and dissipate the moisture.