Coolant sensor issues. help!

[RamNation91]

2012 Ram 1500 5.7

need a little help or pointers,
my truck was having issues starting but no engine light or codes when i scanned it. ended up changing the coolant sensor & now starts no problem but my EVIC coolant gauge won't drop below 100F even when i disconnected the sensor. & i believe is it causing bigger issues, transmission seems hesitant while shifting sometimes.

any advice is good advice, Thanks!!

 

[madtrucker2016]

maybe a restart on the main computer try disconnecting battery and also tie the neg +pos cable together for 25 mins see if that does anything might set into relearn the main computer