Car has failed emissions 4 times now 2 times Nox was 2.01 standard is 2.00 latest results HC 0.69 CO 11.07 NOX 2.64 nox is all that fails everytime. Ive ran premium gas, used octane booster, is there
any adjustments like R16/1 or anything I can doto make it pass?

Thanks in advance for any help