So I have an ‘05 350z with 110xxx miles, it had been struggling with idle at 1500-2500 rpm but after that it would be fine. During a drive today it decided to completely lag at any rpm and seemed as if it was stalling but it’s an auto. After getting home and turning the ignition off I heard some can like rattling or popcorn making sound. There’s also a funky smell coming from the car. There are no mods on it. Any guesses as to what it can be?

 

Dying mb?
Seriously - welcome! It could be anything from bad gas to old plugs or a bad coil. Your idle is at least double what it should be it neutral or in gear, so it's time to spend $75 at a good independent shop for a diagnosis. Gl!