what does NOx ppm mean?

[BrandonR18]

yea its OBD1. is there a way to find out what the problem is exactly with out have to just start buying parts...lexus is way proud of their stuff so i cant afford to much...lol

[BrandonR18]

this is what my emisions reads.....(25/25 test)HC ppm= reading 7 allowed 111, CO% 0 allowed .61, CO+CO2% 14.5, NOx ppm 1152 allowed 773.



(50/15) test HC ppm 12 allowed 114, CO% .17 allowed .63, CO+CO2% 14.4, NOx ppm 686 allowed 853