Fascinating. Of all the 'sharp' smells in my environments over the years, diesel exhaust has always been one of the absolute harshest to me. Feels like it's actively damaging my lungs perceptibly in real time. It's the primary reason I keep my car's climate control on internal circulation almost constantly. I flinch whenever I detect the slightest trace.
Maybe I got exposed to a little too much of it as a kid.
I have that reaction to the exhaust that airplanes introduce to the cabin when reversing out of the gate before takeoff. It boggles my mind why all outside air isn't shut off when reversing. I get an instant headache and have difficulty breathing, and I'm generally not sensitive to much of anything.
Maybe I got exposed to a little too much of it as a kid.