My Mom has a 89 3.1 grand prix . I drove it for awhile yesterday the temp gauge never rose up any . Im thinking its either the Temp sending unit . Or maybe the thermastat is stuck open . Is there a way to tell if the thermastat is sticking without putting it on the stove in a pot of boiling water . Or would this be somethinge else besides the temp sending unit or thermastat . Thanx guys .

 

ttt:lala:

 

how long were you driving it for?

 

probe the engine coolant temperature sensor with your voltmeter

you should see XXX amount of volts

if you see that, then you know your gauge is most likely the bad sour banana

 

whoops made a slight error

you'll have to find out which wires out of the ECM go to the temp gauge

probe them to make sure they are giving power and ground

if they are, the gauge is bad

if not, you have either bad wires, bad ground, short circuit, or bad ECM

 

I drove it about 7 miles . Then went in somewhere for about 20 min came back out and drove it 7 miles home . When I got to the store , I was just thinking , well , I didnt drive it far enough to warm it up , but then I was thinking my car's gauge would have move up some . So then when I drove it home ,l I kept watching it and it never moved .

 

Thankyou man .

 

no problem