Cold Start Sputter - No Boost - SaabCentral Forums
*
Home Saab Pictures Saab Classifieds Saab Dealer Listings Saab Forum Saab Forum


Go Back   SaabCentral Forums > Saab C900, 1979-1993 & '94 Convertible (C=classic) > C900 Workshop

C900 Workshop Classic 900 (1979-1993 & '94 Convertible) Technical Forum.

SaabCentral.com is the premier Saab Forum on the internet. Registered Users do not see the above ads.
Reply
 
Thread Tools Display Modes
  #1  
Old 15th August 2007
Mag-X's Avatar
Mag-X Mag-X is offline
Saab Lunatic
 
Join Date: Jul 2003                                                
Location: Portland, OR, USA
My Saabs: 2010 Saab 9-3 2.0T
Posts: 2,524
Default Cold Start Sputter - No Boost

I did a search, but using the words "cold start" brings up almost every thread in the C900 section. I couldn't find one with my exact problem(s).

Starting the motor from a cold start results in one of two scenarios.

Scenario A)
1) Turn the key once: cranks and cranks, but doesn't fire.
2) Turn the key a second time, and it cranks and sputters and shakes, but doesn't actually start
3) Turn three it fires right up, but I cannot touch the gas pedal for a few minutes, or it will stall.
4) Starts running fine, but no boost

Scenario B)
1) Starts up first try, works great, but check engine light comes on.
2) No boost!

Then about 20 minutes later the boost just comes back.
__________________
sudo chown -R us ./base
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2  
Old 15th August 2007
grif900's Avatar
grif900 grif900 is offline
Saab Lunatic
 
Join Date: May 2006                                                
Location: W. Yarmouth,MA. U.S.A.
My Saabs: 1988 900 SPG
Posts: 4,358
Default

Senario A, leads me to suspect the amm.

senario B, suggests a wiring or connector issue(intermittenet problem). Or perhaps a failing amm(though I've never had one die quite like that) is possible. The amm does control the apc.
Reply With Quote Quick reply to this message
  #3  
Old 15th August 2007
c900's Avatar
c900 c900 is offline
Saab Lunatic
 
Join Date: Jul 2005                                                
Location: Tronno, NSW, .au
My Saabs: 81 8V 900T, 91 2.1 900i, 90 9k 2.0 Carly
Posts: 3,058
Default

Quote:
Originally Posted by Mag-X
I did a search, but using the words "cold start" brings up almost every thread in the C900 section. I couldn't find one with my exact problem(s).

Starting the motor from a cold start results in one of two scenarios.

Scenario A)
1) Turn the key once: cranks and cranks, but doesn't fire.
2) Turn the key a second time, and it cranks and sputters and shakes, but doesn't actually start
3) Turn three it fires right up, but I cannot touch the gas pedal for a few minutes, or it will stall.
4) Starts running fine, but no boost

Scenario B)
1) Starts up first try, works great, but check engine light comes on.
2) No boost!

Then about 20 minutes later the boost just comes back.

Is this on an 8V or a 16V car? I've found that on my 8V cars, esp. the older few with the fully-pressurised tank and no pre-pump, the engine(s) start but revs drop right down for a few seconds after letting go of the key, then come back up to normal, and I've determined that's just because of the fuel pressure still coming up as the pump pressurises the tank and starts to push fuel through the lines to the fuel distributor.

In 16V cars I wouldn't expect this sort of thing to happen, or in the 85+ 8V cars, since they all have the double-pump setup, however my theory could be off-track for your problem.

When I first got my 81 turbo car (8V non-apc) it had the wrong fuel pump relay. Instead of the special version with the extra terminal-50 connection, it had the version used in the non-turbo cars. I changed that for the right version (salvaged from the 83 turbo that I'm stripping [took more stuff off it yesterday!]), but it didn't seem to make a lot of difference.

Craig.
__________________
Craig Dewick - Tronno, NSW, .au - Flickr - 1981 8V 900T, 1990 9k 2.0 Carlsson, 1992 2.1 900i - RIP Moose.Parts and their top-quality customer service!
Reply With Quote Quick reply to this message
  #4  
Old 15th August 2007
Mag-X's Avatar
Mag-X Mag-X is offline
Saab Lunatic
 
Join Date: Jul 2003                                                
Location: Portland, OR, USA
My Saabs: 2010 Saab 9-3 2.0T
Posts: 2,524
Default

It's a '92 16Valve. I have noticed that it seems to happen more when the tank is full. I haven't been through that many tanks of gas though, so it could just be in my head.
__________________
sudo chown -R us ./base
Reply With Quote Quick reply to this message
  #5  
Old 15th August 2007
Mars700 Mars700 is offline
Active Member
 
Join Date: Aug 2007                                                
Location: Long Island
Posts: 45
Default

Un hook the AMM and tell me what happens please..
Reply With Quote Quick reply to this message
  #6  
Old 15th August 2007
Mag-X's Avatar
Mag-X Mag-X is offline
Saab Lunatic
 
Join Date: Jul 2003                                                
Location: Portland, OR, USA
My Saabs: 2010 Saab 9-3 2.0T
Posts: 2,524
Default

Sure thing. What is an AMM?
__________________
sudo chown -R us ./base
Reply With Quote Quick reply to this message
  #7  
Old 15th August 2007
Mars700 Mars700 is offline
Active Member
 
Join Date: Aug 2007                                                
Location: Long Island
Posts: 45
Default

Quote:
Originally Posted by Mag-X
Sure thing. What is an AMM?
Air Mass Meter..

Reply With Quote Quick reply to this message
  #8  
Old 16th August 2007
jglavin's Avatar
jglavin jglavin is offline
Saab Lunatic
 
Join Date: Jan 2007                                                
Location: Denver
My Saabs: '13 Focus ST
Posts: 1,577
Default

I've heard a simple check of the AMM is to pull it off the filter, and have someone put the key in the run position... then look inside the AMM to see the small wire heating up and glowing orange...did the check on my 92 once and sure enough it glowed.

edit - I believe it only lights up for a sec and then goes out, so if you do the check look closely.

Last edited by jglavin; 16th August 2007 at 12:19 AM.
Reply With Quote Quick reply to this message
  #9  
Old 16th August 2007
Mag-X's Avatar
Mag-X Mag-X is offline
Saab Lunatic
 
Join Date: Jul 2003                                                
Location: Portland, OR, USA
My Saabs: 2010 Saab 9-3 2.0T
Posts: 2,524
Default

OK. I'm at work right now. I'll go do that on my break.
How should it react with it disconnected?
__________________
sudo chown -R us ./base
Reply With Quote Quick reply to this message
  #10  
Old 16th August 2007
silversaab96's Avatar
silversaab96 silversaab96 is offline
SaabNut!
 
Join Date: Jun 2005                                                
Location: Victoria, Australia
My Saabs: '90 900T - '75 96 - '90 9000T - '99 9-5
Posts: 442
Default

You haven't been spray/steam cleaning the engine by any chance in the past day or so, or gone through big puddles? Had all these symptoms after cleaning the engine.. split or degraded rubber boots (on the back of the various electrical plugs) can do it, as can water in or around the top of the AMM.. just a thought....
__________________
All things are possible..except perhaps, skiing through a revolving door.
Reply With Quote Quick reply to this message
  #11  
Old 16th August 2007
Mag-X's Avatar
Mag-X Mag-X is offline
Saab Lunatic
 
Join Date: Jul 2003                                                
Location: Portland, OR, USA
My Saabs: 2010 Saab 9-3 2.0T
Posts: 2,524
Default

Quote:
Originally Posted by Mars700
Un hook the AMM and tell me what happens please..
Done. Runs like ****.
__________________
sudo chown -R us ./base
Reply With Quote Quick reply to this message
  #12  
Old 16th August 2007
Mag-X's Avatar
Mag-X Mag-X is offline
Saab Lunatic
 
Join Date: Jul 2003                                                
Location: Portland, OR, USA
My Saabs: 2010 Saab 9-3 2.0T
Posts: 2,524
Default

Quote:
Originally Posted by silversaab96
You haven't been spray/steam cleaning the engine by any chance in the past day or so, or gone through big puddles? Had all these symptoms after cleaning the engine.. split or degraded rubber boots (on the back of the various electrical plugs) can do it, as can water in or around the top of the AMM.. just a thought....
No. There hasn't been a heavy rain in weeks.
__________________
sudo chown -R us ./base
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Bookmarks

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the SaabCentral Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools
Display Modes

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 08:10 PM.



Powered by vBulletin® Copyright ©2000 - 2014, vBulletin Solutions, Inc.

top of page | sitemap | email us



copyright © 2003 - 2011 saabcentral.com, All rights reserved http://www.whiter.co.uk - valid xhtml - valid css
SaabCentral is an independently run website and is not affiliated in any way to Saab Automobile AB.


Garage Plus vBulletin Plugins by Drive Thru Online, Inc.