96 Ranger runs cold - little heat

[bobber1]

Hi all:
Have a 1996 Ford Ranger 2.3 4 cyl 5 speed manual. Experienced a situation where the temp barely moves to the normal and is fluctuating between cold and normal. Seemed like classic case of thermostat stuck open so changed that. The problem still exists. I put the obd II on it to monitor the water/coolant temp. On the obd the temp fluctuates between 160 and 185 or 190ish. This is even after running/driving the truck for minimum 30 minutes with the hvac control in the off position. The heater blows lightly warm at best but that seems to be due to the lack of water temperature. I have seen some posts pointing to the water pump as the culprit, but would that account for the low temps I'm seeing on the obd II?

Thanks in advance for the help!
Bobber

 

[Tbars4]

What temp tstat did you install?

 

[meyek91974]

I had this last year

it was pretty flat as far as temp change, but didnt overheat. I changed the thermostat and since it's not hard flushed the cooling system too.

My old thermostat was designed that in the event it broke/failed, it would "stick" in a half opened position allowing some cooling and flow but wouldnt get warm enough for the heat to work

Easy work ahead except it's flippin freeezin out there

 

[bobber1]

Installed a 192 degree thermostat

I suppose the new one could be bad, but actually the old one I replaced didn't appear to be stuck open. I changed it out anyway, but as mentioned before, that didn't seem to resolve the problem.

Did not flush the system since I'm in the Chicago area and it's damn cold here right now. Flushing was something I was considering, but hoping for a little warm up in the weather first...