headgasket, vacuum leaks - Saab 900 Bulletin Board - Saabnet.com
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]
[Main C900 Bulletin Board | BBFAQ |
Next by Date | Post Followup ]
Member Login / Signup - Members see fewer ads. - Latest Member Gallery Photos
headgasket, vacuum leaks
Posted by JohnK (more from JohnK) on Wed, 19 Feb 2003 11:04:46
In Reply to: help!!!!!!!rough idle!!!!!!!!, dave, Wed, 19 Feb 2003 04:04:51
Members do not see ads below this line. - Help Keep This Site Online - Signup
Rough running and white exhaust at initial start up are frequent headgasket symptoms. It happens gradually and then one day you notice it. After you stop the engine for the last time in a day, the cooling system will still have enough pressure to force coolant into a cylinder. When you start up in the morning this coolant gets "burned off" and goes out the exhaust. If you let it go too long, there is a chance that enough coolant will build up overnight to cause "hydrolock" which can blow a cylinder and create a major mess.
You can verify the problem by checking your plugs. The bad cylinder(s) will have amazingly clean spark plug(s). You might also see a steady stream of small bubbles coming out of the small hose in the collant expansion tank. A shop with a sniffer may be able to detect exhaust in your coolant. Lastly, if the expansion tank is quickly pressurized (well before warm up), you are getting cylinder pressure in the cooling system.
High idle conditions are often due to a vacuum leak or stuck AIC valve.
posted by 216.75.9...
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.
StateOfNine.com
![](/tsn/xyz/stateofninebutton.gif) |
SaabClub.com
![](/tsn/xyz/scnabutton.gif) |
Jak Stoll Performance
![](/tsn/xyz/jakstollbutton.gif) |
M Car Covers
![](/tsn/xyz/mcarcoversbutton.gif) |
Ad Available
![](/tsn/xyz/buttonavailable.gif) |
![](/tsn/images/tsnmap.gif)
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!