I checked the exhausts, under the hood, bottom of the car, etc... couldn't find a plastic bag stuck anywhere.

Recently, after warming up and the heat comes on, I smell burning plastic. Happens 9 out of 10 times I drive the car.

Once I smell it, I turn off the car, get out and pop the hood... the smell is more pronounced in the top right portion.

But I see nothing burning? Nothing stuck?

Anyone have an idea what's going on?

ONLY thing I did recently was top off some coolant (located almost opposite from where the smell seems to be coming from)

 

Did you spill any coolant or overfill the reservoir? Coolant has a characteristic sweet smell that I would agree is similar to the smell of burning plastic. When the dealer topped some of mine off, they spilled some into the engine bay. As the engine components heat up, the coolant began to give off a smell that was sucked into the fresh air intakes. After a drive, I could even smell the coolant outside the car.

 

If you just topped up coolant, maybe check Waterpump?

 

The de-icer chemicals they put on the road here make the exhaust smell like burning plastic.

 

I have a similar issue, but it is only when the heat is on and set to a lower temperature than HI (86, 85, etc..). Turn the heat to HI and see if it still smells. Not a fix, but something I noticed.