I just bought a 90 LS, and to my dismay…it failed TX emissions!? It says my CO% reading is 2.50 when the avg is 1.12 at high speed while my Nox (ppm) is 1641 when the avg 1258. Can anyone tell me what this means and what I can do to fix it? The jerk-off inspector wouldn’t tell me anything.
It’s running rich… Could be that it wasn’t properly warmed up prior to taking it to the smog shop or that they let it sit around too long. Early tegs with one wire O2 sensors are not heated and cool off easily and then they run open loop. Could also be a dirty air filter, bad vaccumn hose, etc. You might be able to fix the NOX if you get it to lean out but you may also need a new cat. If the car hasn’t been modified you can go to the smog ref and you shouldn’t have to pay more than $100.
Chris…
that’s a non-obd car for ya
if you need it done right now, paying someone off is prolly your best suggestion, unless you’ve got some money lying around to do a tuneup i.e. new dist rotor, spark plugs,check and adjust timing- make it LEEEAAANN lean as friggin possible. If you have an adjustable fuel pressure regulator lean that bit(h out. Replace your o2 sensors with OEM honda sensors or for a temporary fix, buy aftermarket ones and then return them after you pass, cause they’re not worth $hit IMO.
oh and check this out Texan
http://www.g2ic.com/forums/showthread.php?s=&threadid=30111&highlight=DFW
what does it mean…lean out? and i wish i could meet up with ya’ll (i live in carrollton). but i have to go up to school. perhaps sometime over winter break…
leaning out is just giving ur car less fuel…however you will need a fuel pressure regulator to do that at the least. Just don’t lean it under “I think” 30 psi or the ecu will throw a code.
As far as the smog problems…it could be tons of different things. If I were you, take it to a smog and repair place and have the guys there look at it. That way they can repair and test at the same time.
BTW when you buy a new/used car, aren’t the previous owner supposed to be the 1 to smog it? It’s that way here in Cali.
HTH
Ken
i never bought a used car before, and he offered to get it inspected for me. but i told him i’d pay a hundred dollars less for the car and i’ll just inspect it myself. seemed like a good idea at the time, but its biting me in the ass now. but i think i got an ok idea bout what to do. thanks for the help guys.
it could be a whole lot of things extreme lean WILL cuase co to go up also. i’ve been an emissions inspector for a year or so and i also have a waiver license so i know what i’m doing. NOX is a representation of combustion chamber temp. CO is Oxides of Carbon which relates to unburnt fuel. but the common misconception is that it is always to rich when CO is high. if the mix is so lean that it causes a misfire you will also have a high co # b/c the fuel was never combusted. runnin lean would also relate to your high NOX levels b/c like a torch adding more air makes the fire burn hotter. i’d say you could be runnin lean but can’t tell just from those gasses. if you can have your car done on a five gas analyzer it makes it easier. as soon as i can get to a scanner i’ll post a nice chart that has all the gasses in relation to air fuel ratio… a good carbon cleanse and tune up usually helps alot.