I went to get my car tested for emissions, and i failed for to high of CO% in both the 15 mph and 25 mph. I was wondering if anyone knew ways of cutting those numbers down. I really dont wanna pay out the ***.... i do have the stock cat on there dont have headers, but have a custom piped 2.25" piping from the cat to a OBX muffler. But i doubt thats the problem...if anyone can help id appreciate it.

 

Is it possible that you could post all your numbers?

CO levels are usually pretty low on properly functionning engines.

DId they test at idle? How were your numbers?

I don't think there is much you can do to trick your engine in producing less CO.
What is happening is that your engine is starving for oxygen. SO you need to look at your o2 sensor, air filter and cat for proper functioning.

Maybe someone here has a cool trick they would like to share.

If it would be HCs that would be high, simply raising the operating temperature of the engine will bring those numbers down.

fs

 

15 mph CO% Limit: 0.62 Reading: 1.23 Result: Fail
25 mph CO% Limit: 0.60 Reading: 1.01 Result: Fail


Those are my numbers im not quite sure the rpms he was at or whatever...but i dont understand why im so far off. I have 14 days to fix it and get it free so thats what i plan on doing but i really dont wanna hvae to take it somewhere there goin to charge me anally. Everything esle i passed and i mean easily it was just the CO i was way over in...i dunno

 

What have you done to your car prior to getting the emission test done?

fs

 

Have intake and exhaust...thats it. And i wasnt doggin the car up there or anything. So i dunno...do you have an idea why they'd be so far off?

 

Yes i do have an idea... You are not burning up the fuel going into your combustion chamber... This means that, on a fuel injected engine, your not bringing in enough air. TO much fuel. So you basicaly need to look at fuel/air management. If HC and CO were high, then we could talk about the cat, but in this case we can forget about it.

What year is you car?

Usually, when you go for emission testing, you need to prepare your vehicle so that you pass.

DO this:

1. change sparkplugs.
2. change air filter
3. I know you won't like this, but change O2 sensor
4. Before testing, go take a nice long drive to make sure your engine is hot.
5. change oil.

fs

 

Oh okay, sounds like ill be doin all that in the next two weeks. I really appreciate all your help...the year of my car is a 1992 SOHC F22A. But hopefully i can get this thing to pass without it, lol no tags which means no driving.

 

well i have went twice now and failed both times... ive managed to pull my 25 mph co% down to pass, but for some reason i cant get my 15 mph co% to pass....what would cause one to pass but not the other...both times i only failed 15 mph co% but i have gotten it down but not far enough to pass