2002 Acura MDX Temperature control

You might have a problem with your air mix motor, its what blends the hot air from the heater and cold air from the a/c to get the exact amount of temperature, you particular vehicle model has had a few of those problems lately.
Aside from that, make sure you manually have the a/c set to off when you set the temperature gauge to full auto, it usually goes on to prevent your windows from fogging but it also throws off the vent's output temperature