overheating, need to change the thermostat?

Hello,

Here is a guide to help you change the thermostat out with instructions in the diagrams below to show you how on your car.

https://www.2carpros.com/articles/replace-thermostat

Check out the diagrams (Below). Please let us know what happens.

had this problem and had to replace the thermostat cost me $34.00

Six cylinder front wheel drive automatic 50,000 miles.

How do you change the thermostat what do you have to remove to get at it?

Hello,
To better assist you, could you please list the engine size? 3.4L or 3.6L engine? Also, the eighth digit of VIN number will be helpful as well.

Thanks for using 2carpros.com!

the VIN number is, 3g5da03e24s58o878 and the engine is 3.4.

Great, thanks for that information. Below are the removal/installation instructions for your thermostat: REMOVAL: Remove the air cleaner and duct assembly. Drain the coolant until the coolant level is below the thermostat. Remove the crossover exhaust pipe. Remove the radiator hose from the thermostat housing. Remove the thermostat housing bolts and clean any sealer from the bolt threads. (Removing the housing bolts)

Remove the thermostat housing and gasket. Remove the thermostat. Clean the mating surfaces. (The removal and installation of the thermostat)

INSTALLATION: Install the thermostat. Install the thermostat housing and gasket. NOTE: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems. Install the thermostat housing bolts and tighten them to 18 ft. lbs. (25 Nm). Install the radiator hose to the thermostat housing. Install the crossover exhaust pipe. Install the air cleaner and duct assembly. Fill the cooling system. Hope this helps.. Thanks for using 2carpros.com!

I am replacing the thermostat in a 2002 Buick rendezvous. I took the necessary hoses loose but no coolant came out? When I checked it before I started the repair there was coolant in the tank. Where did it go?

Just because there is coolant in the reserve tank does not mean the radiator is automatically full. I don't know why you are changing the thermostat but you have other issues there that need to be found. You need to pressure test test the cooling system to find out wheere that coolant went and pray you didn't blow a head gasket already from overheating it.

The vehicle did not have any heat in the heaters at all. Ice cold. that is why the thermostat was being changed.

Not having enough coolant will give the same symptoms.

The coolant was full. It was checked.

You just said no coolant came out when you removed the hoses. That completely disproves that.

Before the thermostat job was started the coolant was checked and it was full. Both in the jug and in the radiator. Don't quite know why it didn't show up anywhere. There was none in the crankcase either.

Need to replace the thermostat on my 2002 Buick Rendezvous. I would like to know what I need to remove and how to remove it so as to have access to the the two thermostat housing bolts?

Remove the air cleaner and duct assembly. Drain the coolant until the coolant level is below the thermostat. Remove the crossover exhaust pipe. Remove the radiator hose from the thermostat housing. Remove the thermostat housing bolts and clean any sealer from the bolt threads. Remove the thermostat housing and gasket. Remove the thermostat. Clean the mating surfaces.

Install the thermostat. Install the thermostat housing and gasket. Install the thermostat housing bolts and tighten them to 18 ft. lbs. (25 Nm). Install the radiator hose to the thermostat housing. Install the crossover exhaust pipe. Install the air cleaner and duct assembly. Fill the cooling system.

We have replaced the thermostat, the vehicle engine does not overheat anymore so apparently the thermostat was bad. We have refilled it with coolant, bled the lines, tightened the radiator cap, checked for leaks but the heater does not heat. Any suggestions?

With the engine at full operating temp, locate the 2 heater hoses where they go into the firewall and feel them to see if they are both hot to the touch.
If you find that they are both too hot to hold, then the heat in that vehicle is controlled by a blend door that regulates heated air flow. it is operated by an electric motor/actuator. The problem can be that the actuator is stripped or inoperative or the door itself could be damaged. This is what needs to be determined by examining the actuator and see if it is responding to heat change commands or not.

Thank you Wrenchtech for your help. It turned out to be the radiator cap wasn't on tight enough to get the water circulating. Now the heater works.

Radiator cap?
About the only thing that is going to cause is coolant loss. It has nothing to do with circulation but has everything to do with the system drawing the fluid from the reservoir when the engine cools down.

Well, that's all it took after we got the thermostat in. That was faulty. If the cap is screwed down tight the coolant doesn't build up pressure to flow. It just escapes the system. This is my last transmission. Again thanks.

Hi, I was reading your response to a 2004 buick rendezvous thermostat issue and I need help with my 2002. from what I have read, there are enough differences between the two 3.4L engines that do not make me comfortable enough to follow the 2004 directions.

My 2002 thermostat seems to be stuck open. The temperature doesn’t pass the 1st hash mark on the gauge and because of that, the heater doesn’t blow warm air. I see where the housing is, but am not sure exactly what I need to unbolt. I have changed thermostats in other vehicles without any issues, but I am intimidated. I don’t want to unbolt stuff without knowing what the torque for tightening is and/if there are is any need to purchase gaskets, etc.

Can you walk me through the ’02 process. I would rather spend the time and do it myself rather than have to take it to a mechanic and pay for the labor for a $15 part.

Ok if you have done thermostats in the past then you know to drain out some antifreeze. Then you remove the upper hose and unbolt the thermostat housing using the two bolts and remove the stat and not how it is pointed put the new stat in and put the housing back on (clean the mating surfaces first) and put the upper hose back on. Now near the hose is a bleeder valve loosen it two full turns (this ensures that there is no air in system, called burping the cooling system) when anti freeze comes out of the bleeder close it fill the radiator and put the cap back on. Start the car and let it warm up keep an eye on the temp so it don't get hot incase you didn't get all the air out. Then when it cools check the fluid level and you are done. Here is a pic to help

I am clear with your explanation, but what do i need to remove to get the housing off. I thought that i read that the throttle body needed to be loosened in addition to an exhaust crossover pipe? are there concerns about any gaskets there or not? from what i saw on my vehicle, i dont think i can get to the housing bolts without removing some stuff.

I didn't find that in the procedure to do this but it is in the way then you may have to but I never mentioned it. I will look again.

need instructions on removal and installation of thermostat

If you follow the upper rad hose to the engine it will end at the t-stat housing. Drain the coolant, remove the upper hose from the housing, unbolt the housing, remove the old t-stat and reverse the sequence.