Yea if it's stuck shut it would/should overheat. As stated above you prolly got a P.O.S. one. Just pull it and do the hot water test with a thermometer.

 

So the temp is correct. And if it did fail it would say open all the time and over cool it. I say change the temp sensor first.

 

You could get it to temperature and try to hold a thermometer of some sort against a rad hose or radiator. It won't be very accurate but I would think it should still get above 150ish if it is really 195 like it should.

 

I swapped out the thermostat and still have no motor temp or temp in the cab heater.

This time I felt the hoses, the top hose is HOT and the bottom hose is ICE COLD.

Any other thoughts?

 

What he said, sounds like your heater core is plugged.

 

Thanks a bunch everyone! I will keep plugging away at it for sure!!

 

If I were to just have the entire coolant system flushed, does that get the heater core as well?

 

If it has never been flushed it couldn't hurt but likely won't clear the heater core and may plug it more. If the coolant is new or still pretty green you can flush the heater core with minimal coolant loss.

 

Sounds good Fester. I don't actually have running water in my heated shop or any kind of drain pit and with the temp sitting about 7 above 0 right now (and that is the high for today) we may have to just deal with this until it warms up a tad.

I assume a shop would do it for us but I don't want to pay for something I could do on my own!!

Thanks again.

 

If your truck is an automatic, let me ask you a question... is your transmission kicking into overdrive normally? Back when my truck was an automatic, I had one of those fail safe thermostats get stuck open on me and the truck never got up to temp and because of that it never kicked it into overdrive. Since there are 2 sensors, that would be a good indication on what the computer is seeing vs what you are seeing. The engine has to be in its closed loop before it will allow the shift into overdrive.