Coolant reservoir is full of 50/50 Coolant that needed deluged, it's not pre deluted. But when I'm driving down the interstate it stays at half way on the engine thermometer but when I'm idle at a stop light or something it slowly starts creeping up, didn't get to the red mark on the thermometer under the dash but pretty close. As soon as I take off again it goes back down to normal. I recently replaced the heater hose because it was leaking, no leaks now and the reservoir stays full. Any idea what this could be??

 

That's a pretty simple one
Your issue is air flow related and therefore with the fans
when you move, even if the fans don't work, you have airflow through the radiator, therefore cooling
idling/at a stop, if the fans are not working, you have no airflow therefore no cooling

 

If your fans are BOTH running at idle once the engine is getting hot (easy check!), I suspect a stuck thermostat.
Known problem, just don't drive any more till the issue is solved, you are risking much bigger and more expensive problems if you do.

 

Ok I looked when I stopped and a large hose that connects to the thermostat housing had come off..

 

It blew off, the clamp couldn't hold it together, so I went to start my car without knowing this and engine coolant low warning came on so I shut it off right away, going to get some coolant and pump pliers and hopefully I can get it back home

 

Now you will need to be careful; was the hose the problem, or just a result from over heating?
My 2 cents are the latter, the hose coming off as a result of the pressure building once the temperature rises.

While you there and before filling up, I should take off the thermostat, and test it in a pan with boiling water.
See if it opens.
Several movies on YouTube on the matter.

15 minutes extra work to be sure on a critical item in the system.

 

Does anyone know if you over fill the coolant reservoir, that this could happen? Or is there an overflow? Just am trying to figure out why this happened. I put the hose and clamp back on, filled it up with coolant and drove it back home no problem.

 

it never reached the red area on the thermometer inside the car, the dial got to about 3/4 and by that time I had parked. And also when I filled the coolant up yesterday, I definetely remember overruling it on accident, could this extra coolant build pressure and blow that hose open? Or is there and overflow valve. That's why I didn't think much of it because I thought there was an overflow valve

 

Can't overfill.
One of the 3 hoses on expansion tank goes to your left front fender, where there is a secondary overflow tank.
If pressure builds, redundant coolant is pushed into the 2nd tank, then sucked back if the engine cools after use.

PS1. The temperature gauge in the dash is considered totally worseless, unless you have the modification kit installed.
PS2. If you still have the plastic thermostat tower (presuming you have a N/A engine), the plastic retainer where the hose 'hooks' might have worn off.
Replacing with a alloy version is the best option for now and the future.

 

I have the allow one. You think I should still replace it and the thermostat housing?

 

You got the alloy one, looking OK, so no need to replace the tower.
On the thermostat, I am not saying it is your problem, but doing a test or replacing it will rule it out as a possible cause for your problem.
As earlier suggested, are your fans running?

 

yes fans are running and there are no coolant leaks after I replaced the heater hose, up until when the hose busted open that was attached to the thermostat housing

 

i went a got a new thermostat just in case, but im testing the old one in boiling water and ill see what happens

 

alright, so I tested both the new one and old one in boiling water, only the new one opened, the old one stayed shut, so can I pretty much rule that this was because of a bad thermostat?

 

In my case it was the exact same, and a new thermostat did solve the matter.
Check your level of coolant after the first couple of rides.
After the first time it should have dropped a bit, even if you burp all hoses as good as you can during filling.
You should be good after the second fill, unless your 2nd tank was pushed empty, in which case it might take several little top-ups to get some fluid in there.
Level will settle some 1/2 inch below the neck of the tank.