Failed Emissions Inspection

Hi all. I failed emissions inspection. I failed for hydrocarbons and NO2, but not carbon monoxide. It has a recent tune up, a new ICU, coil, and I think it runs great for a car with 150,000 miles. It was really cold the day I had the inspection done, maybe my car doesn't warm up enough for the catalytic converter to work. I'm leaning towards replacing the catalytic converter and the oxygen sensor. I was wondering if anyone else had any ideas. Thanks.

oxygen sensor would be my bet.


change oxygen sensor, fill it up with the best gas grade, drive on the freeway for about 30-45 minutes and then go for an emission test, should be alright then.

this trick worked out very well my old 90 galant that used to smoke whenever I would start the engine.

if your exhaust is slightly blowing esspecially before the lambda probe this will put your hydrocarbons through the roof also if you have a cat give your car a hammering before your test to get it red hot ( they work better hot)