Does an O2 sensor effect any performance on a 2008 G35x sedan? It’s bank 1 sensor 1 if so what could happen if not fixed for a while etc?

 

Other than marginally lower gas mileage on my Accord, I never noticed any driveability issues with a primary O2 sensor being bad, likely be the same with any car. But it also gave me a CEL and to pass emissions here I replaced it.

 

Depends on if it's working at all, if it's completely failed and not sending a signal then you're stuck in open-loop mode with abysmal mileage, no cam timing advance, only the base ignition timing advance, and no power.