I just did an entire coolant flush, every bit of it. Took the radiator hoses off and the radiator drain, got every bit of coolant out.. Put everything back together, filled my truck up with 50/50 (coolant and distilled water). Left the cap off and turned the truck on and let it sit in idle. I let it do this for 30 minutes and the temperature gauge won't go past 1/4... So I went driving around for about 30 minutes, and still the temperature gauge stays at 1/4, when it should be at 2/4... Not sure what's going on. I did exactly 50/50, and followed everything to the book on doing a coolant change. No idea why my gauge won't go to normal temp... Any help would be greatly appreciated, I'm at a loss right now

Edit: Forgot to mention, I did blast the heater while doing this. Heat seams to work fine also

 

Sounds to me like your thermostat may be opening too soon and not allowing it to warm up fully.

 

You should not use extra water with pre-mixed coolant, it's already the correct concentration. Now, yours is diluted which will degrade your freeze protection, should that be a concern in the winter where you live.

The in-dash gauge is pretty much a mechanical idiot indicator. It just accepts data from the PCM and then moves to an appropriate band based on that data. To see if you have an actual concern with the cooling system, you need to use your scan tool and read the temperature that the PCM is seeing from the CHT sensor.

Depending on the year (not supplied), a thermostat that is open and causes an extended warmup or insufficient coolant temperature will set a P0125 DTC. Have you checked for any pending codes?

 

Oh I'm sorry it was super late last night, not sure why I typed it out like that. I meant to say that I ended up with 50/50, half coolant and half distilled water.

I haven't tested for any pending codes, I'll do that today! Great advice and help

Edit: I just read that when I did the clean out, a lot of junk could have made my thermostat get stuck open. So I'm going to go out there and drain the coolant again, clean the thermostat really well, then put the coolant back in. Hope this works, will keep you updated!

Update: Nope, I took the thermostat out and it is in the closed position. So it's not stuck open Took boiling water to it and it opens and closes just fine

 

I took my thermostat, put it on the stove and when the water started to boil, the thermostat opened up. Then I took it out and it closed. Do you still think its the thermostat? I have no idea whats going on

 

Only thing I can think of is do what Project said and use a scan tool to read the live ECT data. Be sure to clean the lip that the thermostat contacts to make a good seal, as well. Normal operating temp will be 190-195 F.

 

Okay edit: scratch everything I just said. I have no idea why my truck is running cool... I'll try and get my hands on a scan tool. I went to Orelly's and their tool only works if your check engine light is on...

 

Do you know what the tool is called, and how to do this? I have no idea how to do any of this, just need some direction! Thanks

 

Okay, well just updating everyone. After a couple days, the meter slowly went to normal operating temperature. Not sure why it slowly got better day after day but after a few days now its perfectly fine... No idea why it wouldn't just do it at the start. But all is good now and I'm leaving it at that. haha.