Smells like burnt rubber when I turn up the heat in my car.
Check the cabin filter. I found mine completely blocked with a mouse nest. It kept air from flowing and the blower control module was overheating.Eventually took out the solar separation relay on mine. Also make sure your cowl vents aren't all packed with ice and snow.
Also could be oil dripping on the exhaust manifold. If you run synthetic, it smells slightly like burnt rubber.
Does it tend to go away while moving? If so, it may be that it is no longer sucking fumes form under the hood.
I also suspect my blower motor is on the way out. It's been too cold for me to get in and check it out. I want to pull the motor and if nothing else clean and lube it up.







