Question about 1999 Buick LeSabre

1 Answer

How do u change a thermostat in a 99 buick la sabre, there is only cold heat coming out of the heater

Posted by on


1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 20 achievements.


    An expert that got 10 achievements.


    An expert that got 5 achievements.

  • Buick Master
  • 17,970 Answers

The thermostat is used to control the flow of engine coolant. When the engine is cold, the thermostat is closed to prevent coolant from circulating through the engine. As the engine begins to warm up, the thermostat opens to allow the coolant to flow through the radiator and cool the engine to its normal operating temperature. Fuel economy and engine durability is increased when operated at normal operating temperature.

CAUTION Never open, service or drain the radiator or cooling system when hot; the system is under pressure and will release scalding hot coolant and steam which can cause severe burns and other bodily harm. Also, when draining engine coolant, keep in mind that cats and dogs are attracted to ethylene glycol antifreeze and could drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantities. Always drain coolant into a sealable container. Coolant should be reused unless it is contaminated or is several years old.

  1. If necessary, unfasten the retainer and remove the upper engine cover.
  2. Disconnect the negative battery cable.
  3. Remove the air cleaner and duct assembly.
  4. Partially drain the engine cooling system, into a suitable container, to a level below the thermostat.
  5. Disconnect the upper radiator hose from the water outlet.
  1. If necessary, detach the electrical connections from the throttle body assembly.
  2. Unfasten the water outlet attaching bolts, then remove the water outlet.
  1. Remove the thermostat. Remove and discard the gasket.
  1. Thoroughly clean the manifold water inlet and water outlet mating surfaces. Inspect the water outlet for corrosion or other damage, and replace if necessary.
how do u change a - 2f45efd.jpg

Fig. 8: Exploded view of the thermostat and housing assembly - 3.8L (VIN C) engine


Fig. 9: Thermostat and water outlet mounting - 3.8L (VIN L) engine shown


Fig. 10: Exploded view of the thermostat, gasket and housing assembly - 1997 vehicle shown

To install:

  1. Position the thermostat into the intake manifold with a new gasket.
  2. Install the water outlet to the intake manifold with RTV sealer. Tighten the attaching bolts to 20 ft. lbs. (27 Nm).
  3. Connect the radiator hose to the water outlet housing.
  4. If necessary, attach the electrical connections to the throttle body assembly.
  5. Install the air cleaner assembly, then connect the negative battery cable.
  6. Refill the engine with the specified type and amount of engine coolant. Start the engine and check for coolant leaks.

I hope this helps; remember to rate this post. Good luck.

Posted on Oct 05, 2010


1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi there,
Save hours of searching online or wasting money on unnecessary repairs by talking to a 6YA Expert who can help you resolve this issue over the phone in a minute or two.

Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.

Here's a link to this great service

Good luck!

Posted on Jan 02, 2017


Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

97 Buick la sabre won't start cold weather. I tried starter fluid into breather port EFI engine. will a heater element dip stick help.

If you're using the correct oil viscosity, have a good battery and good spark plugs, you shouldn't need an engine heater.

Jan 13, 2018 | Buick Cars & Trucks

1 Answer

I have a 2005 buick le sabre and the heater sometimes works and sometimes doesn't

Sounds like the heater matrix is blocked hence you have a little heat until you turn the blower on whereby it comes out cold because there's no more. Get someone to check the temp of the heater hoses when running and check for an airlock in the heater. These can be tricky to clear. Make sure the coolant is full at all times.

Nov 19, 2014 | Buick Cars & Trucks

1 Answer

When I put the heat on the drivers side blows warm air but the other side blows cold air

you may have dual heat controls, one for the driver and one for the passenger . my 98 La Sabre had them.

Mar 04, 2014 | 1996 Buick Park Avenue

1 Answer

Do i have to bleed the cooling lines after i replace the heater core in a 1984 la sabre

Not on and 84. Fill radiator and let it run until the thermostat opens and top off the water , put cap back on and fill the coolant tank to proper level.

Jan 24, 2011 | Buick LeSabre Cars & Trucks

1 Answer

My 1995 buick le sabre battery died no when heater is on it blows cold air how do i reset

if the heater is not working then you need a thermostat or heater core

you cannot reset the heat

charge you battery or take it to auto zone and get it tested

Dec 05, 2010 | 1995 Buick LeSabre

1 Answer

2000 buick la sabre was working very well. it sat

try dumping some gas line antifreeze into the tank

Jul 28, 2010 | 2000 Buick LeSabre

1 Answer

The check engine light is coming on my 99 buick la sabre

Take it to a local auto parts store (Autozone, Murray's, Checkers, Napa) have them hook up a scan tool to get the diagnostic codes, write them down and post them here so we can further assist you. There are many reasons that can cause the check engine light to come on.

Jan 11, 2010 | 1999 Buick LeSabre

1 Answer

Temp. need for 2007 la sabre ltd 6 cyl

norm is 82-86 degrees in hot climate 72- to 76

Jan 03, 2010 | 2000 Buick LeSabre

1 Answer

Lots of cold air from 2000 buick la sabre

Be sure to keep an eye on your coolant level. If there's a leak, then it'll just get low again and return with no heat. There'll also be a chance on overheating your car if it's low on coolant.

Make sure if you're adding water, that it's DISTILLED water. It's free from impurities and will be much better for your system.

It's actually recommended to use 50/50 diution of antifreeze and distilled water. You can buy this already pre-diluted, which is easiest. Or you can buy the full mixture of antifreeze yourself and mix it 50/50 with the water.

Feb 10, 2009 | 2000 Buick LeSabre

Not finding what you are looking for?
1999 Buick LeSabre Logo

1,854 people viewed this question

Ask a Question

Usually answered in minutes!

Top Buick Experts


Level 3 Expert

79865 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22326 Answers

Ronny Bennett Sr.
Ronny Bennett Sr.

Level 3 Expert

6927 Answers

Are you a Buick Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides