Not necessarily. The catalytic convertor doesn't do much about NOX. Excessive NOX is affected most by timing and cylinder chamber pressures. I would check the vacuum and mechanical timing advance systems. Since your #'s are on the high side I would suggest a complete tune-up replacing at a minimum the ignition wires, spark plugs, and air filter. Check (and adjust if necessary) the timing and the valve clearances. Wouldn't hurt to also check the compression on each cylinder to make sure you aren't carboned up. How is your gas mileage? If it is low you might also need a tweak on the mixture screw and/or fix some vacuum leaks. As Dave S says, DMC SoCal is probably the best place to go. David Teitelbaum --- In dmcnews@xxxxxxxxxxxxxxx, "daveswingle2" <swingle_dmc@...> wrote: > > DMC Cal is probably the best at this, but based on the numbers you're probably looking at a new catalytic converter. > > Dave S > > --- In dmcnews@xxxxxxxxxxxxxxx, aphawrldch@ wrote: > > > > > > > > > > Well...4066 just failed smog. Sure could use some help as to where to go to fix this. Not to go... What do I replace? > > > > %CO2 > > > > Test 15 MPH 1496 RPM meas 8.5/8.3 > > > > 25 MPH 2451 RPM meas 9.0/7.6 > > > > > > > NO (PPM) > > > > 15 MPH Max 1148 Ave 434 Meas 854 > > > > 25 MPH Max 978 Ave 357 Meas 1172. FAIL! > > Any suggestions would be appreciated! Would LOVE to just have to change plug wires, air filter, something semi simple. I'm sure I'm just dreaming! But sure am hopeful! > > > > Thanks > > > > Linda > ------------------------------------ To address comments privately to the moderating team, please address: moderators@xxxxxxxxxxx For more info on the list, tech articles, cars for sale see www.dmcnews.com To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnewsYahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/dmcnews/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/dmcnews/join (Yahoo! ID required) <*> To change settings via email: mailto:dmcnews-digest@xxxxxxxxxxxxxxx mailto:dmcnews-fullfeatured@xxxxxxxxxxxxxxx <*> To unsubscribe from this group, send an email to: dmcnews-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/