Hi
Are there any CO Emission percentages, at idle and cruise, specified by Nissan for the 2004 Maxima?
Many thanks

There's no spec from Nissan that I know about, it's just required to meet EPA/CARB standards. To my knowledge that's been 1.2% for all light duty vehicles since (I think) 1981. The EPA driving tests actually go by grams per mile, I think that limit was 15g. EPA and CARB have modified standards for HC and NOx many times since then, but the CO standard hasn't changed for a very long time, I think because it wasn't practical to make cats much more efficient at CO recombination than they already were.