On my 2013 I just noticed that the heat isn't blowing as hot as I would expect. I hit the vents with the temp gun and they are reading around 100 but the passenger maybe a little higher than the driver. When the engine is up to temp I hit the inlet and outlet hoses to the heater core and they are reading around 160. I pulled apart the dash thinking it was the blend door actuator and before removing I turned my temp knob, and the dam thing is moving perfectly. Is it the heater core? If so, wouldn't my two temps on my inlet and outlet be different because of a clog? I checked to see if I had a clogged cabin filter, none present. It seems like people that flush the heater core only fix the issue for a short period of time. They aren't that expensive; do I just replace it and flush and fill the system? Any other checks / diagnosis I can do?