Suggestions for passing emissions...?
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Suggestions for passing emissions...?
Trying to pass emissions with my 10th Anny. Haven't had to actually pass emissions with this car yet as I was living in NC and they only check to see if you have all the original equipment.
Now living in NM I have to pass the emissions test and have failed miserably on the low end.
High Speed 2500rpm
HC 371 Limit 200
CO 2.78 Limit 1.20
CO2 13.4
O2 0.07
Low Speed
HC 1089 Limit 200
CO 2.03 Limit 1.20
CO2 13.1
O2 1.18
For this latest test the car was setup with the air pump connected directly to the catalytic converter, denatured alcohol was added to the gas, and I had replaced the spark plugs, adjusted the TPS, idle speed and mixture.
For tomorrow's test I have replaced the O2 sensor and swapped out another MAF sensor from my previous turboII that had been used when it successfully passed emissions a few years ago.
So I am just looking for any suggestions or things that someone might notice from the results from the emissions test that I can do to correct what ever is wrong.
Perhaps the Catalytic converters are just too old?
Now living in NM I have to pass the emissions test and have failed miserably on the low end.
High Speed 2500rpm
HC 371 Limit 200
CO 2.78 Limit 1.20
CO2 13.4
O2 0.07
Low Speed
HC 1089 Limit 200
CO 2.03 Limit 1.20
CO2 13.1
O2 1.18
For this latest test the car was setup with the air pump connected directly to the catalytic converter, denatured alcohol was added to the gas, and I had replaced the spark plugs, adjusted the TPS, idle speed and mixture.
For tomorrow's test I have replaced the O2 sensor and swapped out another MAF sensor from my previous turboII that had been used when it successfully passed emissions a few years ago.
So I am just looking for any suggestions or things that someone might notice from the results from the emissions test that I can do to correct what ever is wrong.
Perhaps the Catalytic converters are just too old?
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easier
1. make air control valve work correctly
2. pass smog
1. make air control valve work correctly
2. pass smog
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#10
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Those limits are actually pretty high. They are higher than cali or texas.
Being that they dont test for Nox you could lean it out a bit if you had some kind of engine management to lower your hydrocarbons and carbon monoxide. But if you dont have engine management I would just buy a cat that you can install only when you go to take your emissions test.
Being that they dont test for Nox you could lean it out a bit if you had some kind of engine management to lower your hydrocarbons and carbon monoxide. But if you dont have engine management I would just buy a cat that you can install only when you go to take your emissions test.
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Make sure you save the receipt for your new cat. Many states offer an emissions waiver if you spend enough money on emissions-related repairs and the car still does not pass for some reason. I've never lived in New Mexico so I can't tell you if that's the law there, but it may be.
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yes. pumping air into the exhaust ports works much much better than pumping air thru a 3/16" hole into the back half of the cat
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Well I think I am going to get a high flow converter and weld some flanges on it to replace the first muffler on my racing beat full exhaust system and just get rid of the stock exhaust all together.
So my next question is do I need to get a cat that has an air tube port on it?
Or can I just get away with re-connecting the ACV in stock configuration and just leave the block of plate for the split air tube on the manifold?
So my next question is do I need to get a cat that has an air tube port on it?
Or can I just get away with re-connecting the ACV in stock configuration and just leave the block of plate for the split air tube on the manifold?
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Well I think I am going to get a high flow converter and weld some flanges on it to replace the first muffler on my racing beat full exhaust system and just get rid of the stock exhaust all together.
So my next question is do I need to get a cat that has an air tube port on it?
Or can I just get away with re-connecting the ACV in stock configuration and just leave the block of plate for the split air tube on the manifold?
So my next question is do I need to get a cat that has an air tube port on it?
Or can I just get away with re-connecting the ACV in stock configuration and just leave the block of plate for the split air tube on the manifold?
#18
Rotary $ > AMG $
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Well I think I am going to get a high flow converter and weld some flanges on it to replace the first muffler on my racing beat full exhaust system and just get rid of the stock exhaust all together.
So my next question is do I need to get a cat that has an air tube port on it?
Or can I just get away with re-connecting the ACV in stock configuration and just leave the block of plate for the split air tube on the manifold?
So my next question is do I need to get a cat that has an air tube port on it?
Or can I just get away with re-connecting the ACV in stock configuration and just leave the block of plate for the split air tube on the manifold?
The supply of air into the exhaust and preferably into the space between the bricks is necessary to provide oxygen for the Oxidation reaction that occurs in the rear brick to Oxidize the hydrocarbons.
Note the emphasis on oxidation. You need oxygen for oxidation. On our FC's, it comes primarily from the air pumped into the exhaust (on rotaries) and from the NOx reduction reaction in the front brick. Rotaries have inherently low NOx due to the relatively slow combustion speed and relatively low combustion temperatures.
So, on our rotaries, controlled by 1980's era technology, the pumped air. (exhaust and split air) is necessary to successfully oxidize the Hydrocarbons.
I recommend a universal 3-way w/air cat. The one I use is available from Autozone, part number is 38734, brand is Maremount, 2-1/2" inlet/outlet rated for a V-8 of 7.8 liters and over 8000# vehicle. I have passed emissions 3 times with this one cat. In a couple of weeks, I will try it for a 4th time.
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