KAmey1970

I suprisingly passed NJ inspection with my 83 shark. I put on the TB/WP with only a few stupid mistakes. I had to adjust the parking brake and clean some electrical connections.

I was worried about emissions...but I did ok, I think.

Here are the numbers on the report. Can someone fill me in what they mean?

Gas Standard Reading
NOx 1146 387
HC 152 78
CO% 0.86 0.63
CO2% 14.5
Ox% 0.2

I am happy I passed, but wonder if these numbers are all good? Not knowing what they all mean, I am not sure if there are any warning signs. After my 914 gave nothing but problems, I am expecting the other shoe to fall with the shark. (though I am not worried about rust, like with the 914)

Then again, feel free to tell me to shut up and enjoy the car!

docmirror

Gas Standard Reading
NOx 1146 387
HC 152 78
CO% 0.86 0.63
CO2% 14.5
Ox% 0.2


This might look more appropriate. The columns indicate the type of measured gas by the probe, the next column indicates the maximum allowable reading for your car, and the last column indicates the readings actually taken during the test. Somewhere on the form the words "PASS" should appear for those gases that have a standard, like NOx.

The numbers for your car look fine, however the % of CO(Carbon Monoxide) is near the limit. The CO is reduced by modern high temperature catalytic converters. What this shows is that; 1-Your Cats are getting worn out, and will need replacement at some point. 2-The car was not fully hot when tested.

Catalytic action occurs when the exhaust gas reaches about 550 degrees. If the car is not driven for about 20-25 minutes prior to test, the catalytic action is not completely controlling the action of the CO, and some of it is escaping out the tailpipe. Since gasoline contains about 20,000BTU/pound, and the engine only dissipates about 80% of that, the rest must be reburned(slow burned) in the catalytic converter.

The NOx, and HC are fine. HC is left over products of combustion of auto gasoline such as Benzine. The cats also help to reduce HC by oxidizing the remaining HC and converting the gas to CO2+H2O(carbon dioxide and water).

All of this process depends on a near stoichiometric balance between fuel and air. That's what the O2 sensor does in your exhaust system. The engine must have some left over Oxygen in the exhaust to burn the remaining gases in the cats. A misadjusted O2 sensor, or too much raw fuel will damage a cat and make it less efficient at converting the products of combustion to less harmful gases. In an extreme case, a cat fire can occur with too much reburning going on.

Enjoy the car!

Doc

deliriousga

Was the engine cold? Mine were close to that last year, but this year I made sure I drove around and ran a few errands on lunch before going to get the test. Here are the numbers after warm:

25/25 Test
Allowable Reading
NOx 1014 768
HC 144 59
CO% 0.92 0.04
CO2% 13.8
Ox% N/A

50/15 Test
Gas Allowable Reading
NOx 1110 849
HC 148 51
CO% 0.83 0.02
CO2% 13.4
Ox% N/A



So, does anybody know what the difference is between the 25/25 test and the 50/15 test?

touque

here are mine from a post a few weeks back. I compared my 2004 to 2005 numbers. I had chips installed in 2005.

.................15mph............................25mph
HC 2004.....53..................................68
HC 2005.....19..................................17

CO 2004....0.16................................0.16
CO 2005....0.06................................0.04

CO2 2004..15.5................................15.3
CO2 2005..15.0................................15.0

NOx 2004..59....................................85
NOx 2005..97...................................130

My car sat a lot before I purchased it and had the emissions in 2004. Since I've owned it, it's been a daily-driver for me.