higher coolant temperature
2012 jeep patriot 2.4L 189k miles
recently the temp gauge goes slightly passed halfway point while driving roads and highways. obd app is showing up to 225F. it will drop some when the fan kicks it but generally runs around 217F to 221F. it drops significantly to 206F when i turn the heat on with high fan. turned back to cool and it will go up. outside temp is 70F.
I tried burping, massaging both hoses which were hot. did this for about 30 min. highest while parked was 208F. i did notice the reservoir gradually fill up but coolant in radiator did not drop. after all that the temp still went up after driving. oil is at safe level but needs to be changed.
thoughts? TIA.
UPDATE: thermostat is stuck closed. end up having mechanic do and flush coolant. joy....