I hope someone can help me here,

I have a 2014 Ram 1500 5.7L Hemi and a few weeks ago the Electronic Throttle Control light came on. I noticed that when this light came on i started having issues with it starting but once started it ran fine but also noticed that after a few minutes the ETC light would come on and my temperature gauge would drop all the way to down, like it quick working and I no longer see the ECO popping up during normal driving..Everything I read said that I had to replace the throttle body to fix the issue. I replaced it yesterday and I disconnected the negative battery cable and re connected it to have it relearn.It had trouble starting at first and i let it run for a few minutes. I turned it off and it started fine and then proceeded to drive it. I drove it for a few minutes and the ETC light came on again, lost my temperature gauge and noticed the ECO not popping up, Came home and had trouble starting it again.

Can anyone tell what the problem is or where I go from here?

Thanks