95 Firebird Overheating

Hi there
I did not drive my car for a week. Then one day I took it out and found that the pointer on the temperature gauge was pointing all the way to the right(over heat zone). The heater was not working either and was blowing cold air instead. The pointer on the temp gauge was very responsive and fluctuated. If I would step on gas it would show high temp but if I'd step down the gas, pointer would come down in the middle.

I dont understand wat is the problem here.
Is the engine really overheating or its the thermocouple or some sensor ?

please advise

thank you

temp sending unit?my gauge runs to a wire.That wire runs out the dash,to the motor.On the drivers side head,is a device called a temp gauge sending unit.It could be in a different location,dont quote me,but the name of the part should be the same.You make it sould like the gauge acts funny,like when you throttle it,it immediatly notices a temp change,and then when you let off,it immediatly goes back down..

Hey I think I know what your problem is. When I bought my car it had in the dealers lot for about a week. Well I got home found out that there was no heat and only blowing cold air. Number one make sure you do not have orange anti freeze like I did. That has known to goop up and clog the heater core. It also made my thermosat stick. I power flushed the radiator that seemed to helped. I then took it to jiffy lube and had them replace it with green. They power flushed the radiator 8 times before it finally cam back out green. My car does not overheat any more and it also has outstanding heat. This may be your problem checked my temp sending unit and it was fine so if yours ends up being fine check out what just told you about.

first make sure the coolant is not low that could cause yer problem or transam95's idea cuz hes right that orange stuff sux the guy that thought it up needs this
:bricks1:

And don't forget to check the thermostat itself.