How do I change the thermostat on a 89 sunbird

blower resistor could be bad, or your thermostat on the rad

You can put the thermostat in a pot of water on the stove
& put a thermometer in there to test,to learn something,
that's a good idea

Your still going to install a new one every 6 to 8 years

You don't have to drain much to remove it from the car

Warm up the car and pay attention to the coolant reserve tank.
If you see bubbles raising up from the bottom of the reserve tank then you has exhaust leak at the head gasket,
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The shop method is a coolant system pressure test and hydrocarbon dye test.

Call trans shop for this I dont know the exact answer but Im sure a good trans shop cold tell ya

2.2L Engines - 1987-91 VEHICLES



Fig.: Thermostat location and mounting - 1987-91 2.2L engines




2.8L and 3.1L Engines



Fig.: After unfastening the retaining bolts, remove the outlet and lift out the thermostat - 3.1L engine shown


Hope helps (remember rated this).

get a mechanic to have a hands on look ,could be a multitude of problems from head gasket to cooling fan

open the radiator cap and you can pull it out

My apologies for the delayed response.
I am going back to answer - unanswered questions. I have only been on this site for the past 4-months. Questions Posted have exploded (+55%) since joining.
I do not know if you still need this information, but I am answering it either way.
CLICK on the following LINK. It has the Belt Diagrams you will need.
If you would: Before Clicking: Let me know if this helped you, or if you have any additional information or questions. Feel Free to contact me at FixYa.com!
Again my sincerest apologies...
Thanks.

http://www.2carpros.com/car_repair_information/year/1989/make/pontiac/model/sunbird/1989_pontiac_sunbird_drive_belt_routing_diagram.htm

The radio will be installed in the location of the tape player.

Metra Kit# 89-30-3310


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When the fuel system can"t provide any more fuel it will cut off (similar to electronic speed cut) to save itself from leaning out. Its not a good idea to take that hose off as it will boost itself to death, it has no way of controling how much boost is run and it'll be a matter of what goes first, the engine or the turbo.