96 lumina running cold

96 lumina 3.1 186,000 is barley getting above the 100 degree mark on the temp gauge. I would think this would be an indication of the thermostat stuck open. Any thoughts?

before I rip into it I had some thoughts....

I replaced the water pump last year, because of a leak, and the belt.
Antifreeze is full, I replaced it when I installed the new water pump.

Is there any other visual checks or tests that I can do to pin point the cold running cause? I guess I could stick a meat thermometer lol into antifreeze after the car is warmed up. What should the temp be? 195, 185, stock thermostat I think.

Thanks

Kirk

The temp in the radiator is cooler than the engine, it should be scanned and the temp read directly, if under 180 or so, the thermo is bad, if running at 190-200, suspect dash gage or dash sending unit in block.

Is the engine is getting warm and the guage isn't reading, or are the radiator hoses only getting luke warm? If the hoses are getting hot, then you have a bad guage sender switch. If the hoses are only getting luke warm, then your t-stat is stuck open. Make sure you are familiar with bleeding the cooling system if you're going to replace it yourself. If you don't get the air out of the upper end, you could smoke your motor.

Thanks for the reply guys, I should have explained it a little better. The temp inside of the car is warm,but not hot. I will check the hoses to see if they are hot or just warm. Could the heater core be partially blocked? Could you explain a little bit more about how to make sure that I get all the air bubbles out of the cooling system? I have never heard of air bubbles, or pockets smoking your motor.

I am still thinking that the stat is stuck open.... I have heard guys that would tap on top of the stat housing to free it. If the stat is stuck open it could mean I have some junk in my antifreeze?

I will check back

thanks again


Kirk