1979-1993 & 94 Conv [Subscribe to Daily Digest] |
[Main C900 Bulletin Board | BBFAQ |
Prev by Date | Next by Date | Post Followup ]
Member Login / Signup - Members see fewer ads. - Latest Member Gallery Photos
Yup. Posted by Justin VanAbrahams [Email] (#32) [Profile/Gallery] (more from Justin VanAbrahams) on Mon, 10 Sep 2012 14:56:47 In Reply to: Re: suggestion/help for failed CA smog, kenS [Profile/Gallery] , Mon, 10 Sep 2012 13:42:46 Members do not see ads below this line. - Help Keep This Site Online - Signup |
Timing is key on these cars. California's current policy is that timing must +/- 1 degree from factory specification which is 16 degrees, so you can be at 15 or 17 and still pass. Some shops don't know the law has changed, and still think it's +/- 3 degrees. Find one of those shops! ;) Timing has a direct and tangible impact on NOx.
Carbon deposits in the combustion chamber can also cause high NOx by trapping heat and decreasing burn efficiency, but it sounds like you have that taken care of with the Redline. It *might* be worth trying a Seafoam treatment. If your mechanic has one of those sweet fiber optic inspection scopes you can probably look around inside a little and see what it looks like.
Vacuum leaks can definitely mess with your mixture, although IME such a leak has to be very, very bad in order to completely trash a smog check. It is worth checking your injectors to be sure the o-rings are still sealing well - it's a source of leaks frequently missed. Another culprit is often the charcoal canister, although if you got to the point they did the pressure test on your gas tank, chances are it's ok.
On the subject of injectors, if yours are original, they could be end of life. Ancient injectors don't atomize the fuel properly, leading to all sorts of emissions issues.
I would not trust a couple year old AMM. Not to say it is definitely the problem, but man I have nothing positive to say about rebuilts. They don't seem to last.
I would not sweat the cat. It is probably not your problem - more likely something else is out of spec, which is causing the cat to operate at low efficiency.
Healthy O2 sensor?
posted by 12.195.130...
No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.