2009 RX 350: Heat blows cold at idle, hot while driving
2 Answers
correct, because while driving the water pump rotates the water from the block and trades with the cooled water in the radiator. So, while this exchange is going on you have heated coolant from the block goes to your heater core and that is why you feel a change in your heater, based on the temperature setting for the blend door. It fades off though if you just sit and idle. Because the coolant isn't trading spots
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Thank you, but no. Please let me clarify. Yes, your correct, that is how a heating system works in an automobile. However, when I said it blows cold, I mean COLD (30degrees) immediately ie. (off the throttle coming to a stop). Its winter. Having warm/hot air ONLY while driving/moving is not normal by any means.