Strange smell from heater

For the past few weeks, I've noticed a strange smell coming from my vents when I first start the heater. It lasts for a few minutes then goes away. It smells like rubber burning or bugs burned up by a light bulb. Any ideas?

 

When was the last time you changed your filter? Maybe its clogged up.

 

Have you checked the cabin air filter recently? Something might have gotten in there and not lived to tell the tale... The cabin air filter is behind the glove box. You need to take the glove box out to check it but it's an easy project, 5 minutes.

 

Yup, that would be the first thing I would check. The cabin air filter.

 

Stop farting.
Jk if all else fails go buy industrial strength car freshener in concentrate form

 

I've also been dealing with a odd smell for a while now (most of the winter). I would only smell it on my short commute home from work. Ive recently noticed when I leave work I have a few birds fly out from under the hood. Opened hood and found some bird droppings throughout the engine bay. Figured I am smelling burnt bird crap. Got some dog/cat/bird repellent from lowes and soaked the engine bay with it. Had to leave the truck parked outside of the garage for the night because that stuff smells terrible. The next couple days the whole truck smelled bad but I haven't noticed any birds anymore or the smell and that's been over a month that I sprayed it down.
I havent replaced the cabin filter yet and it has 25k on it. Changing it might have fixed my smell but regardless I needed to get those birds out before they built a nest and did more dmaage.