96 mystique temperature gauge is not moving. Earlier in the day the gauge seemed to be working fine went up to the middle. Now it has barely moved and never makes it to the normal range.

That's odd.The coolant flow is basically backwards from earlier chevys but still anything wrong should make it get hotter. I would have to try a winter front,cardboard or similar in front of the radiator and see if the temp comes up,indicating a faulty stat,seems unlikely but ...

no vacuum at the temperature gauge?or gauge went south?

If it flickers, it's a wiring problem.

Temperature gauges will not work properly unless there is water in the radiator. For the light to come and the length of time it takes to work I would be checking the coolant level at the radiator cap first then checking the operation of the temperature sender unit.

you should find it on the intake manifold just behind where the upper radiator hose attaches to thermostat housing

This has got blown head gasket written all over it. How many miles are on the vehicle. Whens the last time the thermostat was changed?

A blown head gasket or a large air pocket in your coolant system. Have a block check done to see if your head gasket is blown

ok mine did this untill i got an air pocket out of the coolent system then it was find.

shift safety lock not disengaging,holding it in park,temp gauge may just be temp sender,you can disconnect and earth out the temp wire to see how the gauge moves to see if its ok and its the sender

there should be a dial to control the center vents. i believe its in between the vents or just below it. it should have blue and red marks on it. move the dial towards the blue indicator and the air should now be cool. in cold weather, move this dial towards the red indicators for warm air. you can adjust temp at these vents by moving the dial between red & blue.