Okay, so I replaced the thermostat and put in new coolant. I also replaced the thermometer sensor because it seemed to be reading higher than the reading I was getting with an infrared thermometer. After all of that I'm still getting a higher reading on the thermometer (About 250(F) when the infrared tells me ~175) and after a while the reading from the infrared climbs up to about 230 just from idling for a while (I turned it off before it kept going). What should my next step be?