air temp charge sensor

got my car where it will start and idle-kinda- keeps pullin a check engine light

so i checked the codes and came up with a 54 and an 85

the 54 was the air pump

the 85 was the air temp charge sensor- noticed that this was unplugged and not hooked up

i have a gt40 lower and it doesn't have a spot for this sensor-

dumb question but is it important- what is its fuction- why is it there

i know on the 94-95 cars this sensor is on the intake tube but i dont where where to put it in my 91

its late and im ramblen on

thanks in advance for any help
scott