Defroster fogs up windows.

[Court M3]

sounds like it. Blower motor runs right? Mine does the same, but blower does not run at all.

[Sean]

Ok, just wanted to get a second opinion on this.

I'm currently using ym dad's 1990 535i. When the car sits after being driven, sometimes the driver's side of the lower portion of the windsheild is fogged up. Then when you try to use the defroster, the windows just fog up. Starts with the front driver's side of the windsheild and moves on back the drivers side windows and eventually the rear window starts to fog up.

bad heater core?