went for e test today. failed. got a 90 integra, with a b16, with hi flow cat. i just bought it. heres the numbers. @2500 rpm HC PPM Limit 200; reading 292 CO% Limit 1; reading 4.24 NO PPM N/A RPM 2659 DILUTION:16.26 @Idle HC PPM Limit 200; reading 345 CO% Limit 1; reading 2.91 NO PPM; N/A RPM 894 DILUTION:15.73 I was just wondering how bad these numbers are. it went with no tune up. oil in the engine was still a gold color. should i change the o2 sensor along with a tune up?,based on these numbers. or just do a tune up.