You're correct: A 93 Civic LX does not have an EGR system,
according to my Chilton's.

This seems like a helpful site:
http://www.aircare.ca/index.php?repinfo-glossary.php . See
especially
"Causes of Excess Emissions."

It puts a lot of emphasis on an improperly functioning EGR
system causing
high NOx , but it lists a few other causes, too. None are
the PCV valve.

http://www.interro.com/techgas.html#anchoreleven states
similar.

An improperly functioning PCV valve may cause high CO, which
you don't have.

What is a PCV valve "catch can"? Did you remove the PCV
valve?

"vairox" <nothere@spammasters.com> wrote
> thanks guys... the O2 sensor was replaced by a shop the
> last time it
> failed (in july 04) and it failed with harder NOX and a
> higher amount
> of HC, though it was still in the legal limit....
>
> no ECU codes...
>
> might install a magnaflow direct fit replacement, if i can
> get them to
> confirm it is california smog/noise legal...
>
> sort of stumped cause i have another inspection coming up
> in june or
> july.... i am now using the proper OEM NGK plugs, did some
> intake
> cleaner throught the booster, idles much better, drives
> smoother...
> cleaned a lot of carbon off the pistons.
>
> you guys know what effect a PCV catch can would have on
> emissions? i
> know it wouldnt do squat on NOX, thats temp related....but
> any others?
>
>