My SO has an 01 LS430. Recently she has noticed a issue with the heating system. When the car is moving, the heater puts out normal hot air as it should and keeps it at the temperature selected. The problem arises when the car stops (as at a stoplight). The air turns cold. As soon as the car is moving again, it blows warm air. It does not seem to make any difference how the control panel is set (eg. outside air, recirculation, mode, etc). The really interesting aspect of this is.......if the car is stopped and the transmission is put in "Park", it continues to put out warm air. If the transmission is in gear, the air is cold when the car is stopped.
I need to get her to check the coolant level but the whole transmission thing makes me think it is something else.
Anyone have any thoughts?
Thanks
Rod