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 | Post Followup ] Member Login / Signup - Members see fewer ads. - Latest Member Gallery Photos
Re: Boost Stutter
Like This Post: - Subscribe to Daily Digest for this Bulletin Board
Posted by Ari [Email] (#2847) [Profile/Gallery] (more from Ari) on Thu, 10 May 2001 11:12:51 Share Post by Email
In Reply to: Boost Stutter, Bill Cannastra, Thu, 10 May 2001 10:06:36
Alert me when someone posts in this thread:
Members do not see ads below this line. - Help Keep This Site Online - Signup

Boost stutter and fuel cut-off are two very different feelings. The stutter feels like the engine is misfiring, and power levels off and the engine runs a bit rough.
Fuel cut-off is very abrupt - the engine completely cuts out for a few seconds. If you're accelerating hard (as is normal under high boost), the engine cut-out will throw you against the seatbelts hard. It isn't a smooth transition.

The most common reason for boost stutter is ignition. First, check the gap on your spark plugs. If the gap gets too big, the plug can't make a spark at high boost, and the engine misfires. If the plugs look even slightly suspect, replace them with the exact NGK specified in the manual. No substitutions. Gap the plugs (new, or the old ones if they look good) to the exact gap specified in the manual or on the decal under the hood. Don't assume the plugs come properly gapped from the parts store.

If your DI cassette is on its way out, one sign could be misfiring at high boost because the cassette isn't producing as high a voltage as when it was young. Possible, but spark plug gap is most likely.

If you are truly hitting fuel cut-off, again, I wouldn't look at an exhaust leak. That is soley due to intake manifold pressure and the fuel-cutoff switch. If the boost needle is being buried in the red and you hit fuel cut-off, inspect the hoses to the wastegate actuator for holes and splits, and make sure the actuator linkage is working properly.

As to the exhaust leak - I've seen quite a few cars with the stud broken off, but there is minimal to no leakage. If you are getting a leak, you should be able to feel the pulses or hear the noise even at idle. But I don't think it would cause the symptoms you speak of.
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!