I recently bought my 2012 Dodge journey 3.6 L. The temp readings indicates 231 degrees in idle on the screen and just pasted 1/2 on the gage. On the road it indicates as high as 246 degrees with the gage about 3/4. The lower the speed both temp indicators start coming down. i put an infrared thermometer below the intake manifold on the underbelly at the block; the temp reading is around 210-214 degrees. The radiator was rodded out a new thermostat/housing and a new temp sensor, with pretty much no change. Besides the temperature reading appearing to be high, what bothers me most is the fluctuation of temperature. The fans works full speed and there is no evidence of excess pressure build-up or erratic behavior. Things seem normal, help

 

I have a 2012 Journey Crew with 137000 miles and just went thru a similar scenario. As you know though it could be any number of things but when it comes to sensors - in Chrysler products if they are not OEM they will not work well - just my experience and many others I have read. Having said that, mine would act the same as yours especially in high heat days 80+ ambient temps. I had my system flushed out at around 100,000 miles and that is when my problems started. Wide temp swings, high values, etc... mine went as high as 246 on a 1000ft climb up a small mountain - freaked me out. Only after installing a NEW radiator did my problem resolve itself. Flushing/cleaning wasn't good enough and with a new radiator its back to the way it was when new. I rarely go as high as 219 now - usually I'm in the low 205-210 range.

 

is the engine oil cooling housing,