!! CA SMOG !! questions ~ Thanks

Hey all and thanks for your answers, in advance.
I recently took my '89 XJ in for a SMOG test 'only', i was one of the lucky few that was chosen, and failed for just the 25 mph NO @ 1462 when max is at 875. I've been doing my research and have come to these conclusions: I'm gonna replace spark plugs, do a cooling system flush (upgraded to an open system when I first got the truck), run a bottle of fuel system cleaner, clean throttle body, Air filter, was gonna change to synthetic oil next change(doing that early), and check the O2 sensors, as well as the EGR valve.
total test results:
test rpm HC (ppm) CO (%) NO (ppm)
15 mph 2040 24~(max 123) .10~(max .73) 772~(max 1015)
25 mph 1663 26~(max 103) .02~(max .10) 1462~(max 875)

Oh i'm running 30" tires otherwise everything else is stock... Being that my CO% is so low I don't think that its the cat, and i tend to think either EGR or O2 sensors what do you all think? As for the other stuff it has been needed to be done so it will get done.. Again thanks all for your time and comments!

How old the Catalyst converter? I had same similar on my 1989 VW Jetta GLi and end up failed smog. They told me Catalyst converter is bad. I bought high flow catalyst converter and went re-test smog again. Got passed the smog test.

I had a '95 that had failed from high NO. It was due to a lean condition from a vacuum leak. The CCV tube that goes to the top of the valve cover had split. I would check all over for vacuum leaks before replacing the cat.

an 89 could be due for an o2 sensor, but it could also be time for a converter or both

'89 XJ total test results:
test rpm HC (ppm) CO (%) NO (ppm)
15 mph 2040 24~(max 123) .10~(max .73) 772~(max 1015)
25 mph 1663 26~(max 103) .02~(max .10) 1462~(max 875)


Ok my last smog on my 90 XJ was as follows:
15 mph - 26(hc) 0.08(co) 47(no) @1711 rpm
25 mph - 22(hc) 0.08(co) 76(no) @1685 rpm

two years ago I gross poluted because of NO... I replaced the O2 sensor, the coolant temp sensor (under the intake-on the block), and finally the Cat conv to make it pass. Typically with High NO the cat converter is bad, regardless of what the CO is doing.

I would recomend checking the O2 first, then the coolant senor on the block, and do a pre-test insp...most places are $20 and go from there.

Scott.

california emissions laws are gettin kinda silly. if you live in an urban area you'll probably have the tighter dyno tests to deal with. the advice here is good...and if you don't have the money for the repairs take a look at the smog website for the state...they will help pay for stuff with certain conditions. good luck.

damn im glad i dont live in california. there's no way my jeep would ever meet emission standards.

yea, glad i dont live in cali either......unfortunately i have other things to worry about (rockets, mortars, rounds, IED's, etc. . .) so i think i'd take a smog check every year. but i'll still live in WA before anyplace else