I passed emissions!

Just to let everyone know, my 91 Civic passed emissions with flying colors!
The new cat dropped my CO, hydrocarbon, and oxides of nitrogen down to
practically nothing. A dramatic difference! Even though carbon dioxide
levels don't count they do measure them and they were way down as well.

Hopefully I can drive the Civic until my van is paid off. My daughter
is 13 and it would be a great car for her to learn with.

Just an aside...even though emissions testing is a pain I wholeheartedly
support the program. I think Maryland's plan is fair - $14 for the first
test, if you pass you're good for two years. If you fail the second test is
free and they give you a list of troubleshooting ideas. Subsequent tests
are $14 and they end up giving you something like 6-8 months to correct the
problem. If it still won't pass you can get a 2 year waiver if you can show
repair receipts for at least $450. Sure it costs money, but if you pass
(like most people do) it's $14 every 2 years. A paltry sum when you
consider the benefit to the environment. If you fail you may have to spend
a few bucks, in my case about $350. But I did get a tuneup and a new cat
out of the deal. My car's running great and I've minimized my contribution
to air pollution. Win-win.

Thanks again for all the help from the folks here at alt.autos.honda!

 

If I remember correctly, CO2 is measured to indicate if there are
significant exhaust leaks in the system. CO2 is a normal product of burning
a hydrocarbon. If the levels are too low, then it indicates that there's a
leak and that the other numbers are probably artificially low since not all
of the exhaust gasses are reaching the test station's probe.

Eric

 

Numbers please! ppm and %, before and after.

I have a vested interest in this, since after nearly 250K miles my cat's
toast. I passed by ONE (1) ppm on NO two years ago. HC ond CO were still
very low.

Next test for me is this summer, and I expect to fail with my original cat.

Did you use an aftermarket cat, and if so, how'd it fit?

 

CO2 is an indication of good combustion. You want HIGH numbers. In the
ASM2525 tests common in North America, CO2 is used as a datum.

That's called "dilution". That's where ambient air characteristics are
compared against exhaust gases. It's pretty complicated.
http://www.pacode.com/secure/data/067/chapter177/subchapFtoc.html

 

Sounds like the smog test in California about 10 years ago - no big deal as
long as you took basic care of your car. Today, it is obnoxious. There are
different types of tests, testing stations and at a cost of $50 per test
pass or not. Lots of fraud in the past that has been addressed by more
procedures. To appease new car buyers, DMV allows for a "smog abatement
fee" in lieu of a smog for the first 5 years of a new car. Smog cert (or
abatement) became a revenue source for the state instead of a clean air
initiative - I hope MD stays simple...