Alright today I hopped in my 2001 Cherokee to go home from work. I turned the heat on after about 3 miles of driving and a terrible plastic/ electrical smell came out. I shut it off and couldn't smell anything with the windows open and after I got home, I didn't smell anything in the engine bay or by the brakes. Any thoughts on what it could be?

 

Is your coolant pretty fresh? When coolant gets extremely foul it has that burning electrical odor to me. Maybe your heater core is leaking nasty coolant?

 

I am interested to hear what other members say about this.
I experienced the same exact thing in my 2000 last winter when I had my heat on, but it was only once and a while.
Someone had mentioned it might be a connector down by the blower motor, but I never ended up figuring it out, before the smell went away.

I am thinking it might start up again this winter

 

The coolant is fresh. I've read up and found that it could be the blower motor, resistor packs, wires, etc. any additional feedback or experiences would be great

 

I would start by checking all the wires related to the heater and the blower motor if you only smell it when the heater is on. Also check out the blower motor relay under the dash behind the glove box. It sounds like you have a wire or a connector that is burning.

 

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When I smelled this exact thing it was the wires going to the switch that turns the blower on. The 4 position switch next to the vent and temp controls.

When I took it apart the insulator was all charred and crumbled when I touched it. So I carefully insulated it with rubber ans put it back together. No problems since.

 

Thanks ill give it a shot !

 

I saw this on a eagle talon. The blower motor switch ended up having a melt down