Originally Posted by mikey918
I have a smell that is only when the heat is on, and when the car is warm. It smels like someting burning, then electrical burning, then something. Not sure what. I also notice I seem to lose small amounts of antifreeze from the tank when I use the heat for a winter. Any correlation?
It could be oil seeping from around the valve cover gaskets on the rear head. That can get down onto the exhaust manifold. That gives off a strong smell. Your heater blower may be leaking somewhere or the smell is going up out of the hood to the intake openings and into the car'* inside.
It might be the resistor pack if you have manual blower controls or the blower control module if you have the automatic temperature with digital readout. The BCM is a power transistor on a heat sink; it might be smelling due to overheating. Do the speeds work okay?
It could be a connector at the resistor pack or blower module overheating due to corrosion. That melts the plastic giving a sour smell/taste.