Engine temp / heater operation (or not) - GM Forum - Buick, Cadillac, Chev, Olds, GMC & Pontiac chat


Buick When starting new posts, please specify YEAR, MAKE, MODEL, ENGINE type, and whatever modifications you have made.

Reply
 
 
 
Thread Tools Search this Thread
Old 01-23-2014, 10:41 AM   #1
Senior Member
Posts like a Camaro
Thread Starter
 
Join Date: Apr 2004
Location: Land of Lincoln
Posts: 1,107
Thanked 5 Times in 4 Posts
scottydl is on a distinguished road
Default Engine temp / heater operation (or not)

One feature I really like about my '00 LeSabre is that the temperature gauge setting will show an actual number for engine coolant temperature. It'* made me aware of a possible problem anyway.

How hot should the coolant get when at full warm on these Buick'*? Mine has a hard time (or takes a really long time) reaching 150 degrees which seems pretty low. I would think these cars would run around 160-180. It hangs out in the 140'* during my daily commute, which is about 15 minutes of mixed city/highway driving. Should be plenty of time to get the engine to full operating temp I would think.

While a cool-running engine usually seems fine, 145-150 barely gets the HVAC heat blowing lukewarm air. It has been COLD where I live (right now -3 with -22 windchill) this winter! I have to leave the heat setting on HIGH constantly, just to barely (and slowly) warm the inside of the car. Air is noticeably warmer if/when the engine temp reached 155-160, but that has been rare.

I topped off the coolant level last week, so that'* fine (it was a bit low when I first noticed lack of heat). I'm thinking possible problem with heater core, but first I wanted to get a consensus on engine temps.
scottydl is offline   Reply With Quote
Old 01-23-2014, 10:50 AM   #2
Senior Member
True Car Nut
 
jwfirebird's Avatar
 
Join Date: Dec 2009
Location: western,ny state
Posts: 9,616
Thanked 563 Times in 481 Posts
jwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond repute
Default

thermostat is stuck open, stock temp is 195, should come up to temp fast (within a few miles) and stay there even in this cold
jwfirebird is offline   Reply With Quote
Old 01-23-2014, 11:49 AM   #3
Retired Administrator

True Car Nut
 
GunsOfNavarone's Avatar
 
Join Date: Apr 2009
Location: Williamsport, PA
Posts: 2,856
Thanked 167 Times in 129 Posts
GunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud of
Default

Lower Intake Manifold (LIM) gasket failing is the most common reason a 3.8L or 4.3L GM engine runs cooler than it should. Replacing the thermostat typically masks the issue for a few days, them back to cooler running temperature.

You may want to do a cooling system pressure test.
GunsOfNavarone is offline   Reply With Quote
Old 01-23-2014, 11:53 AM   #4
Senior Member

True Car Nut
 
2kg4u's Avatar
 
Join Date: Sep 2006
Location: Windsor, Ontario / Detroit, Michigan
Posts: 4,804
Thanked 220 Times in 181 Posts
2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of
Default

Quote:
Originally Posted by GunsOfNavarone View Post
Lower Intake Manifold (LIM) gasket failing is the most common reason a 3.8L or 4.3L GM engine runs cooler than it should. Replacing the thermostat typically masks the issue for a few days, them back to cooler running temperature.

You may want to do a cooling system pressure test.

While gasket failures are common, the first thing I would look at when the cooling sytem is not coming up to temperature is a failed thermostat. Replacing a failed thermostat does not mask the problem, it fixes it.

Always start with the easy stuff first.
2kg4u is offline   Reply With Quote
Old 01-23-2014, 12:00 PM   #5
Senior Member
True Car Nut
 
jwfirebird's Avatar
 
Join Date: Dec 2009
Location: western,ny state
Posts: 9,616
Thanked 563 Times in 481 Posts
jwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond repute
Default

i would think it would make it run hot more than cold. but neither my yukon nor my bonnie(either time of twice) made the temp do anything different. just got misfire codes and ran like crap. i have however had a number of stuck open thermostats over the years and it always made the temp do exactly as he states
jwfirebird is offline   Reply With Quote
Old 01-23-2014, 12:11 PM   #6
Retired Administrator

True Car Nut
 
GunsOfNavarone's Avatar
 
Join Date: Apr 2009
Location: Williamsport, PA
Posts: 2,856
Thanked 167 Times in 129 Posts
GunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud ofGunsOfNavarone has much to be proud of
Default

Roy/ Justin,

Can't explain why, but on the 3.8L and 4.3L, with a failing LIM Gasket in a condition of not getting up to operating temperature in the winter, any changes to the cooling system mask the real issue for a few days. Change the thermostat, heats up good for a few days. Change the water pump, heats up good for a few days. Then the issue returns. Makese no sense to me, but I have seen it numerous times. Change the LIM gasket and no more issues with not running hot enough in the winter.

Post #10 and #13 of this thread is a good example of the above issue:
https://www.gmforum.com/chevrolet-17...-issue-306133/
GunsOfNavarone is offline   Reply With Quote
Old 01-23-2014, 12:19 PM   #7
Senior Member
True Car Nut
 
jwfirebird's Avatar
 
Join Date: Dec 2009
Location: western,ny state
Posts: 9,616
Thanked 563 Times in 481 Posts
jwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond reputejwfirebird has a reputation beyond repute
Default

guess it would be accompanied by coolant loss that you cant find
jwfirebird is offline   Reply With Quote
Old 01-23-2014, 04:32 PM   #8
Senior Member

True Car Nut
 
2kg4u's Avatar
 
Join Date: Sep 2006
Location: Windsor, Ontario / Detroit, Michigan
Posts: 4,804
Thanked 220 Times in 181 Posts
2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of2kg4u has much to be proud of
Default

Quote:
Originally Posted by GunsOfNavarone View Post
Roy/ Justin,

Can't explain why, but on the 3.8L and 4.3L, with a failing LIM Gasket in a condition of not getting up to operating temperature in the winter, any changes to the cooling system mask the real issue for a few days. Change the thermostat, heats up good for a few days. Change the water pump, heats up good for a few days. Then the issue returns. Makese no sense to me, but I have seen it numerous times. Change the LIM gasket and no more issues with not running hot enough in the winter.

Post #10 and #13 of this thread is a good example of the above issue:
https://www.gmforum.com/chevrolet-17...-issue-306133/

Or, it could be a failed thermostat. I like to start with the easy stuff first.
2kg4u is offline   Reply With Quote
Old 01-25-2014, 08:28 PM   #9
Senior Member
Posts like a Camaro
Thread Starter
 
Join Date: Apr 2004
Location: Land of Lincoln
Posts: 1,107
Thanked 5 Times in 4 Posts
scottydl is on a distinguished road
Default

Well here'* what I can tell you all for now... I replaced the thermostat today, and the temp is much more normal (180'*-190'*) now after a full warm-up. I will say that it still took a good 5-10 minutes of idling and 5 minutes of driving to get the temp that high. Heat is working great for now. I'll see what happens the next few days.

I did notice a bit of moisture on the bottom side of the oil cap (I'm talking a few clear drops), and a bit of gunk that came out of the radiator when I pumped out coolant for the T-stat change, which I then later dumped back in. Here'* a couple photos of the residue left behind in the jug, after I poured the the coolant out... anything suspicious, or just typical brown Dexcool buildup?



Attached Thumbnails
Engine temp / heater operation (or not)-th_dsc05742_zpsa4c2e7d0.jpg   Engine temp / heater operation (or not)-th_dsc05739_zpsf0379f58.jpg  
scottydl is offline   Reply With Quote
Old 01-25-2014, 09:12 PM   #10
Senior Member
Posts like a Camaro
Thread Starter
 
Join Date: Apr 2004
Location: Land of Lincoln
Posts: 1,107
Thanked 5 Times in 4 Posts
scottydl is on a distinguished road
Default

One more bit of strangeness... the old thermostat appears to function properly. See images. It was closed at room temperature, and opened after I put it in water and boiled. (That was a test I always wanted to try and never had before.) So I'm not sure what the problem was when this thermostat was still in the Buick, since it'* working now...



Attached Thumbnails
Engine temp / heater operation (or not)-th_tstat-closed_zps54dfc76d.jpg   Engine temp / heater operation (or not)-th_tstat-open_zps9f7af92e.jpg  
scottydl is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Engine quit during operation Mamba1 Bonneville GXP/ Northstar Powered Cars 4 04-30-2010 02:43 PM
AUTOMATIC A/C-HEATER SYSTEM -COMPONENT DISCRIPTION and OPERATION Toddster Specifications and General Information 0 03-24-2009 11:33 PM
heater blowing cold and temp display flashing, + other prob bonnbuddy 1992-1999 1 12-04-2007 08:00 PM
Engine Electrc Fan Operation on 94SE mikeblue94 Everything Electrical & Electronic 1 05-31-2004 09:50 PM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not 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 Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 10:42 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.