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if you have a b16 with all the emissions controls still in place you should be ok. a functioning cat is required. in fact, if the place that does the inspections for you is a highway patrol outfit they can write you a ticket for the gutted cat since that is blatant tampering with the emission controls of your vehicle.

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hahah yea i just got back i went to a shop wehre i no the owenr he was like ill pretend i dont see that gutted cat lol.....but i failed the test heres whee i failed....my HC(PPM) WAS 194 ITS SUPPOSED TO BE 188......MY CO% IS 1.48 ITS SUPPOSED TO BE 1.00 AND MY NOx(PPM) is 3234 and its supposed to be 2188........i dont no much about this stuff but will a stock cat pass me?

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Sorry, I like performance mods out the wazoo, but the emission controls stay installed on my ride. I enjoy clean fresh air and with the current state of the environment I think it can use all the help we can give it.

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slowly, region by region Ohio is adding emission checks to allow you to register your car. It will soon enough be just about every region.

Odd since they eliminated them in Southwestern Ohio at the beginning of the year.

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Analytical Chemistry (the quick and dirty):


"my HC(PPM) WAS 194 ITS SUPPOSED TO BE 188......MY CO% IS 1.48 ITS SUPPOSED TO BE 1.00 AND MY NOx(PPM) is 3234 and its supposed to be 2188"


"But I'm serious when I say I have no idea what those numbers mean"


The units:


PPM is short for Parts Per Million

% is short for Parts Per Hundred


The use of these units is similar to the labeling on your beer, e.g. 12% alcohol by volume means there is 12 ounces of ethanol for every 100 ounces of beer; by volume means they never weighed the beer, they only measured how much space it occupied at some temperature. The units of volume are arbitrary and only matter in that they must be the same, i.e. ounces with ounces, gallons with gallons, etc.


The acronyms:


HC is short for hydrocarbons

CO is how carbon monoxide is represented in chemistry.

NOx is short for nitrogen oxides




Hydrocarbons are any molecule consisting of only hydrogen and carbon atoms. Your gas is a mixture of these molecules, so this part of the test is to see how much gas your engine is not burning, i.e. how rich your air/fuel ratio is.


Carbon Monoxide:


Carbon monoxide is one atom of carbon with one atom of oxygen. It is a natural byproduct of the combustion process. I am not sure why this is part of the test other than to serve as an oxygen sensor or perhaps to see how much gas is being burnt. See, the amount of carbon monoxide produced is a function of the amount of oxygen present. Since the tester cannot tap into your O2 sensors on your car, they might use this to the same effect.


Nitrogen oxides:


Nitrogen oxides are any molecule consisting of one nitrogen and any number of oxygen atoms. In the context of emissions testing, they are specifically referring to nitrogen oxide and nitrogen dioxide. These two molecules destroy ozone. They come from both nitrogen in your gas and nitrogen in the air. Air is roughly 70% nitrogen which you use cannot use to burn fuel since nitrogen does not support combustion. The point of this part of the test is to see if your catalytic converter works properly, it is supposed to reduce the amount of these guys coming out of your tail pipe.


The test results in layman’s terms:


Your exhaust was 0.0194% unburnt gas (HC), 1.48% toxic gas (CO), and 0.3234% greenhouse gas (NOx).




You can thank the University of North Florida for my education and degree in Chemistry.

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