2000 Dodge Dakota Pickup Smoke comes from heater/ac vent

My dad owns a 2000 Dodge Dakota and when he turns on the air conditioner blower, a puff of what appears to be white smoke, comes out of the vent. This is not all the time. It also smells like something is getting hot. Is there something inside the vent system that would cause this? No fuse has blown yet. Thanks for your help.



Turn the heat up and see if it is steam. Heater core leaks in that case.

Does the “smoke” smell strangely like maple syrup?

It smells like something electronic is getting hot. It doesn’t smoke all the time and it very light smoke. I thought it was frost at first.

It’s probably one of the elements in the blower motor resistor block getting ready to go “poof!” Does the blower motor work on all speeds?