The defrost blowing out of the top of the dash to the windshield, particularly the driver's side, is not very strong. In testing the fan, it blows strong to the heater core. However, the air coming out on the other side of the heater core is considerably weaker. From here the weak airstream simply continues to the windshield. So is this simply how the defrost works? I know where the airstream loses it power. It's when it hits that heater core. I realize the heater core will slow down the airstream to some extent. But to what extent I don't know. Is this to be expected, or is it possible that a clean, working heater core is somehow blocking the airstream more than it should?
Other things I have inspected: The outlets, on top of the dash, are clear and clean. Both air ducts are properly attached to the outlets and to the heater box. All deluxe heater controls work properly; fan (all three speeds), inside/outside air, temp., and defrost. The defrost flap inside the heater box works properly. The temp. valve in the heater box works properly. The heater core that was re-cored 5 years ago, is clean with no obstructions, and works fine. There are no obstruction anywhere, including before and after the fan. There are no coolant leaks.
Any ideas would be appreciated.
James
