Burning Smell

So you smell the burning inside the car, but not under the hood? It only happens under load though. It seems like you would have to be able to smell it under the hood. I assume your car doesn't drip any oil on the ground. Nope sorry can't help. Patrick where are you?

 

Was that the first time you drove up a hill that high/long? It may be that the battery control system had never been used that hard before, and it got hot enough to cause some plastic to outgas. That would be normal.

Make certain that the battery cooling vent to the right of the rear seat is never blocked in any way.

 

Is the cabin heater on? Maybe the two PTC electric heaters are producing the smell after a period of disuse.

If you continue to smell this unusual odor, I'd suggest raising up the car sufficiently so that you can look at the entire exhaust system to see if any debris is caught up. If no debris, then look at the engine and transaxle to see if there's a leak where oil can drip onto the exhaust.

 

One windy day, I managed to run over a black plastic garbage bag - empty - that was blowing around. Gawd did that ever start to stink, it melted itself to the catalytic converter

I ended up putting the car on my large ramp at my hobby farm, and using a gasket scraper to scrape all the residue off the catalytic converter.