HFC smell? - hard acceleration

Mandingo

I have a burning smell under hard acceleration that smells like oil or some kind of chemical.

It doesn't have the bad fart smell of a burning clutch. Plus, I get the same smell even when I accelerate in one gear without using the clutch.

I just got back from the dealer and they said it was my HFC. But I just can't imagine it would stink up the cabin this much. I notice it with the windows barely cracked and only under hard acceleration (so I am going 60 or 70 mph when the smell enters the cabin). It seems like there is no way for exhaust gasses to go from the rear of the car and into my window at that speed. My service advisor literally just shrugged when I mentioned this lol

The cats have been on the car for about 4k miles so grease and sht from manufacturing has burned off by now.

I'm wondering if there is oil leaking somewhere I can't see and its getting burned off at high engine speeds. I don't see any oil around the pan or dripping on the ground though.

Again, it isn't an awful smell like the clutch but it smells like some kind of burning chemical. Maybe rubberized undercoating getting hot and outgassing? I'm pretty much clueless here. Has anyone had a similar issue?

Edit:
I just went out and tested this again. I took a friend to get another opinion. He noticed that the smell is similar to freshly fired shell casings which actually is close. I haven't added gunpowder to the gas tank (yet ) so what the heck?

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