Hey Scotty,
I have a brand new 2023 Infiniti Qx60 and if I accelerate hard on the highway with the vents set to circulate inside air, it starts to smell like rotten eggs. Car only has 2100km and using premium gas as recommended. Car is very responsive so performance isn't an issue.
Send it back to the dealer for a diagnosis.
Rotten egg smell usually happens when the cat isnt filtering the pollutants that come out of your engine. Its basically the same smell you get when you run without a cat. I've sadly been there.
Its probably an exhaust leak right before the catalytic converter, thats small enough not to trip the o2 sensors. Check the exhaust before that cat and you might see some soot from where the exhaust gases escape
Sounds like a fuel system / emissions malfunction - Get it serviced immediately.
The dealer may try to tell you "it's alright" but it most certainly not.
BTW, this car has the horrid 9 speed ZF, replace fluid every 20k-30k miles.
So I took it in and they said everything was fine. I took it again on the highway and got the smell again. Thing is it only happens when applying the gas pedal all the way down for a few seconds. Any thoughts? The smell appears to not be as strong as it originally was the first time. Car shows no signs of performance issues and gas mileage is fine.
Go to a different dealer and demand them to remedy the issue, after all, it's a brand new luxury car, even if it's an Infiniti.