Engine runs cold in cold weather - The Saab Link Forums

Go Back   The Saab Link Forums > Saab NG900 '94-'98 and 9-3 '99-'02 Forum > Car Problems? NG900 or old 9-3 Only

Car Problems? NG900 or old 9-3 Only If you're experiencing problems with your NG900 or 9-3, post your question in here. CEL Code or GTFO!

SaabLink.net is the premier Saab Forum on the internet. Registered Users do not see the above ads.
Reply
 
LinkBack Thread Tools
Old 12-10-2014, 11:37 AM   #1
SAABeginner
 
Join Date: Dec 2014
Posts: 2
Engine runs cold in cold weather

2001 9-3, 184k miles. In cold weather, temp gauge runs cool. In town, it gets up to temp eventually. But coming downhill from ski hill, or into an icy headwind on the freeway, gauge runs cool. In some cases, after ~30 min of running cool, temp gauge drops to zero, on comes CEL. The temp of the air from the heater mimics the gauge (cool gauge = luke warm air, normal gauge = hot air). There are dozens of Saab postings and they all point to thermostat. Had the thermostat and temp sensor replaced, seemed to work for a few days, then CEL back and same issue. Mechanic replaced both t-stat/sensor again, same problem returned a few days later. So for 2 years I've just lived with it. Mech has suggested that it is a head gasket issue, that this can cause issues with the temp sensor. But since the heater air seems to mirror the temp gauge, this seems like an actual TEMP issue, not a temp SENSOR issue. Car is acting exactly like the t-stat is stuck open, but I've already replaced it twice.

Anyone have this issue that was NOT a t-stat issue? Can a head gasket cause the car to run cold in cold weather? I don't have any severe head gasket issues as far as I can tell (certainly not consuming lots of coolant).

There have been 1 or 2 times in the summer that the temp gauge dropped to zero and the AC shut down, this was before all the work above, before t-stat/temp sensor were replaced. This was a long time ago and has not happened since, but I don't run the AC that often. Have never had an overheat issue.
viggers is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 12-10-2014, 03:41 PM   #2
Elder
 
Drew in Houston's Avatar
 
Join Date: Aug 2006
Location: PA/MD
Posts: 2,430
Sure sounds like a thermostat issue to me. I'd try a 3rd time but either put it in yourself or have someone else do it. They're cheap and not that hard to do.

Was there ever an incident where you got debris in there or someone put stop-leak in it or something? That stop-leak stuff hardens and can stay in there for a long time and jam things up--I could see it jamming a new thermostat same as an old one. If it has that crap in the coolant you'll want to drain/flush as much as possible. I hate that stuff; it doesn't work in the first place and once it's in there it's hard to get it out.

I can't think of a way that a headgasket or head issue would cause over cooling.
__________________
Co-Founder:
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
First T7 19T turbo setup. First T7 Deka 80lb. injector setup.

Last edited by Drew in Houston; 12-10-2014 at 03:45 PM.
Drew in Houston is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 12-10-2014, 04:36 PM   #3
SAABeginner
 
Join Date: Dec 2014
Posts: 2
Thanks.....had come to the same conclusion about doing it myself. Seems the only way to get it done right these days.

The first t-stat replacement had the cooling system flushed. I've had the car for it's entire life except the first 20k, and never put any gunk into the cooling systems.

I like my mechanic, but until he can explain how a headgasket issue is causing the car to run cold, I think I'll spend the $1500 on something else......like a bicycle.
viggers is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
 
Old 12-11-2014, 06:10 AM   #4
Live, eat, and sleep by TSL
 
Join Date: Aug 2010
Location: Glen Mills, PA (Phila)
Posts: 1,543
It is not a head gasket. First of all, you would have at least some other symptoms of a failed head gasket: oil in coolant, coolant in oil, low power, disappearing coolant, white smoke, oil leaking out of the side of the engine between block and head, etc.

I have purchased a bad thermostat before, so that is certainly a possibility.

The gauge dropping to zero and CEL sounds like a sensor, though. Since you seem to both have bad thermostat symptoms and bad sensor symptoms, I would guess there is another cause than just bad parts. I really like Drew's suggestion about stop leak; it, like many other snake oils, causes way more problems than solutions.

It can't be an entirely electrical problem, since the thermostat is a mechanical part. I agree that you should swap new parts in yourself. It is not a hard job. If they are all gunked up, it explains why they wouldn't work. Aggressively flush the car in that case. Flush many times until water comes out clean and clear with no sediment. If the weather is supposed to be above freezing for awhile, I have ran a car with water in for a day or two and flushed it again later. It was dirty again, even though it had been clean when I flushed it a day before. I think Drew's idea is very good.

You have asked an interesting question, I would be interested in hearing the solution when you find it. Please post your results for academic reasons!
BuHuSPG is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 12-11-2014, 09:01 AM   #5
Elder
 
Drew in Houston's Avatar
 
Join Date: Aug 2006
Location: PA/MD
Posts: 2,430
Quote:
Originally Posted by BuHuSPG View Post
You have asked an interesting question, I would be interested in hearing the solution when you find it. Please post your results for academic reasons!
2nd that, I'm curious what he finds.

I thought about the sensor issue too. That may be a problem as well, but even if it is, it can't cause the symptoms that he's describing by itself.

To cause too much cooling, the only effect a bad temp sensor could have is that if it were reading artificially too high, the controller would then activate the fan in response. And in that case, a properly functioning thermostat would close more, sending less coolant to the radiator (because the heat exchange became more efficient).
__________________
Co-Founder:
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
First T7 19T turbo setup. First T7 Deka 80lb. injector setup.
Drew in Houston is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 12-11-2014, 10:05 AM   #6
Live, eat, and sleep by TSL
 
Join Date: Aug 2010
Location: Glen Mills, PA (Phila)
Posts: 1,543
I am saying a gauge dropping immediately to zero and causing CEL would be a sensor issue. A car that has been running for awhile, even with an open thermostat, would not be at zero on the temp gauge unless it was like, -40 outside.

I think both parts are failing.
BuHuSPG is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 12-11-2014, 07:05 PM   #7
Elder
 
Drew in Houston's Avatar
 
Join Date: Aug 2006
Location: PA/MD
Posts: 2,430
Quote:
Originally Posted by BuHuSPG View Post
I am saying a gauge dropping immediately to zero and causing CEL would be a sensor issue. A car that has been running for awhile, even with an open thermostat, would not be at zero on the temp gauge unless it was like, -40 outside.

I think both parts are failing.
Oh yeah for sure, I wasn't disagreeing with you at all. I think you're right.

All I was saying was that the gauge issue can't be causal for the cold running.
__________________
Co-Founder:
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
First T7 19T turbo setup. First T7 Deka 80lb. injector setup.
Drew in Houston is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 12-12-2014, 08:11 AM   #8
Wagon Shaggin'
Site Moderator
 
Saabeh's Avatar
 
Join Date: Mar 2007
Location: Ayer, MA
Posts: 6,706
I have had trouble with non OEM thermostats, perhaps this is plaguing you as well. Try the OEM Saab thermostat with o-ring available here: 30577561 Engine Coolant Thermostat (89 Deg) - OEM Supplier 26588 - Free Shipping

Looks like the "Saab" branded ones are no longer available, but according to eeuroparts, this is the OE supplier's part. As a side note, I will say that it seems silly that a non OEM thermostat wont function properly but I have experienced the same issue as you, and so has Mike D (who has changed 10x as many thermos as me).
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


Quote:
The only reason it took all day to install was because we couldn't keep our dicks out of each others mouths.
Saabeh is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Old 01-14-2017, 12:53 PM   #9
SAABeginner
 
Join Date: Jan 2017
Posts: 1
Have you been able to fix the problem? My 02 9-3 SE has the exact same problem. . New sensor new thermostat. Code is P0116 cooling performance issue. I also went so far as to test the old thermostat after pulling it out. It worked fine. Replaced it anyway and also tested the new one before putting it in.
JadedWhispers is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the The Saab Link 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:
Vehicle Info.
Enter your vehicle information (year, model, mods)
Insurance
Please select your insurance company (Optional)

Log-in


Thread Tools

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
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -8. The time now is 04:13 AM.


Powered by vBulletin® Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Search Engine Friendly URLs by vBSEO 3.5.2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.
All content is copyright The Saab Link and it's original authors.


 

Garage Plus vBulletin Plugins by Drive Thru Online, Inc.