Emissions test (1 Viewer)

[Gutterpunk]

I know there are other emissions threads on here and I've read a lot of them, but I'm looking for some advice on my specific situation on my 62.

I recently failed a test. I know I need new O2 sensors (been throwing that code for a awhile) and probably new cat converter. I also have a small vaccuum leak.

If I fix those things might it be enough? My CO seems way over where it should be. OR should I plan to do plugs, wires, etc (which I need to do anyway, but don't really have time for in the next few days)?

My results:
HC 3.63, limit 2.0
CO 92.95, limit 30.0

Thanks for any insight.
CO

 

[2mbb]

what's the residual oxygen measurement? the cat needs oxygen supplied by the air pump to work properly. do you know that your AIR system is working?

 

[Gutterpunk]

I don't know about residual O2. NOX is the only other one listed, it passed at 2.1. How do I confirm if the AIR system is working properly? (don't have my manual here.)

 

[rchalmers3]

If the CO is high you won't have a NOx issue.

CO readings give an indication of fuel mixture: Hi CO = rich condition. Rich fuel mixtures burn cooler and counter the conditions that cause NOx emissions.

Of course you should rectify all known problems first: vacuum leaks, exhaust leaks, slow or inactive sensors, etc..... You want the computer to have command of the fuel mixture in order to perform a diagnosis.

When your computer is again in command (all inputs within parameters and the computer is switching frequently) then you can look at the CO and see if there is still a problem. As 2mbb noted, there is a pattern failure on our older rigs regarding the AIR system.

I don't believe that a tune up will directly address your emissions problem, unless the air filter is severely plugged or there is an air leak that is being over compensated for.

You definitely will need the service manual to work out the AIR system testing.
Rick

 

[Gutterpunk]

Thanks. This is very helpful. I'll tinker around and see what comes up on my retest.