The banner above is an advertisment - if it asks you to download software, please ignore.
Site News - 7/1: Members: Log In to See Fewer Ads! | 5/28: SAAB Evolutions/TSN T-Shirts $14
[General | Members | C900 | 9000 | NG900 & OG93 | 93 | 95 | NG95 | 99 | Sonett | Vintage Models | Clubs | Other Cars | FAQs | Gifts | Member Photo Galleries | Member Directory | Classifieds | Manuals | *Buddy Registry | *Mileage Registry | Polls | What's New | Raffle | Photo of the Month | Sponsors]

9000 Bulletin Board
1985-1998 [Subscribe to Daily Digest]
(Search Author's Posts: e.g. Keyword:username)*Members Only

[Main 9000 Bulletin Board | BBFAQ | Prev by Date | Next by Date | Post Followup ] Member Login / Signup - Members see fewer ads. - Latest Member Gallery Photos
Re: 9000 Turbo - 1987 SAAB, Electrical Diagrams - Emmision
Like This Post: - Subscribe to Daily Digest for this Bulletin Board
Posted by Ari [Email] (#2847) [Profile/Gallery] (more from Ari) on Mon, 24 Jan 2005 10:06:24 Share Post by Email
In Reply to: 9000 Turbo - 1987 SAAB, Electrical Diagrams - Emmision, Herman, Mon, 24 Jan 2005 09:45:52
Alert me when someone posts in this thread:
Members do not see ads below this line. - Help Keep This Site Online - Signup

First off, the MAF (Air Mass Meter - AMM) adjustment is screwing you up.

The 380 ohm setting is an INITIAL setting only - usually good enough to get the engine to run. You then adjust the screw until you get the O2 sensor to swing back and forth, from about 0.2 to about 0.9. The critical point is to adjust the screw so that the O2 signal spends 50% above 0.5 volts, and 50% of the time below 0.5 volts. Whatever the end result resistance setting is fine.

It seems that under any load, you're going lean - that's the O2 sensor stuck on 200 mv. The fact that the fuel pressure is increasing is a good sign - it should be. My guess is that the spark plugs look lean.

The only things that control mixture are the O2 sensor and the AMM (MAF). The AMM has 100% authority over fuel, and the O2 sensor only 25%.

What you didn't say was how it failed emissions. If it were running lean, I'd expect the NOx to be way out, but the HC probably OK. If it is indeed running lean (high NOx, plugs showing lean), I would suspect either a vacuum leak on the engine side of the AMM, or a bad AMM. About all you can do on the AMM is to replace it - rebuilt units run about $150.

An important place to check for a vacuum leak is the evaporative charcoal canister. It's mounted in the right front fender, where you can't see it. It has a thin hose running to the throttle body to control the Purge valve, and a fat hose running to a takeoff on the intake plenum for the vapors. Quite often with turbo cars, the pressure blows the hose off the canister, and you don't see it because it's hidden in the fender. Remove the right front turn signal and look in - make sure the hoses are still in place.

As a test, you can try plugging both the thin Purge Valve hose and the fat supply hose from the canister, and see if that cleans up both the idle and the emissions.

posted by 192.249....
Posts in this Thread:
Alert me when someone posts in this thread:
Members do not see ads below this line. - Help Keep This Site Online - Signup
Post a Followup

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.

Name: Member Login / Signup - Members see fewer ads. - Latest Member Gallery Photos
E-Mail: (Optional)
Re-Enter E-Mail: (Confidential & Secure - Not revealed to other users!)
Note: Please check your spam folder for BB responses.

Subject:

Posting rules are simple - No for sale/wanted ads may be posted here - use the site classifieds.
You may not cross-post your message to multiple BBs.
Not permitted: political/religious topics and being disrespectful (personal attacks, insults, etc...).
 Site Members do not see any red text, inline ad links, bottom of page anchor ads, box ads, or anti-spam check.

Message: (please no for sale/wanted classifieds - post those in the Saabnet.com Classifieds)
Links are now automatically made active, no need for any special code (or use the Option Link field below) - don't put links in () or end with a '.'
To add inline images to your post, use [img]http://www.domain.com/img.jpg[endimg] (or use the Optional Image Link field below).

Links are now automatically made active, no need for any special code (or use the Option Link field below) - don't put links in () or end with a '.'
To add inline images to your post above, use [img]http://www.domain.com/img.jpg[endimg] (or use the Optional Image Link field below).
Optional Link: (e.g. http://www.saabnet.com/)
Link Title: (Optional)
Optional Photo/Image Link: (e.g. http://www.saabnet.com/img.jpg)
Photo/Image to Upload: (Please be patient while file uploads)



StateOfNine.com
SaabClub.com
Jak Stoll Performance
M Car Covers
Ad Available

The content on this site may not be republished without permission. Copyright © 1988-2024 - The Saab Network - saabnet.com.
For usage guidelines, see the Mission & Privacy Notice.
[Contact | Site Map | Saabnet.com on Facebook | Saabnet.com on Twitter | Shop Amazon via TSN | Site Donations]

Random Saabnet.com Member Gallery Photos (Click Image)
This is a moderated bulletin board - Posting is a privilege, not a right. Unsolicited commercial postings are not allowed (no spam). Please, no For Sale or Wanted postings, SERIOUSLY. Classifieds are to be listed in The Saab Network Classifieds pages. This is a problem solving forum for over 250,000 Saab owners, so expect to see problems discussed here even though our cars are generally very reliable. This is not an anything goes type of forum. Saabnet.com has been a moderated forum since 1988. For usage guidelines, see the Saabnet.com Mission and Purpose Page. Please remember that you are not anonymous. Site Contact | Site Donations | Other Sites by SP - Poverty2Prosperity.org | Run Club Menlo Park | ScreenBot


Site Members do not see red text instructions, bottom of the page anchor ads, or box ads.
Click here to see all the Site Membership Benefits!