Iat sensor isn't working?

I bought a new sensor and put that in it didn't work i even got a new plug that goes into the sensor and it doesn't work does anyone have any ideas as to what may be causing this, i have a 97 honda civic ex vtec engine
also is sealant necessary when replacing the iat sensor if so what does it do?

Wiring or computer problem if it's not being read and sets a code. Could be bad "new" part, it happens. Installation instructions will tell you if a sealer is needed but generally not.

so what does it do?

http://www.freeautomechanic.com/iat-intake-air-temperature.html

Yeah i'm goingf to exchange the sensor tomorrow for a new one and as far as i know the wires are all connected it seems that when i bought the car there may have been a new plug added because it wasn't the original connection but i made sure the wires were connected, i also put a new o2 sensor in which fixed that problem but everytime i reset the computer it takes 15-20 seconds till the check engine light comes back on i really don't want to take it to a shop to get it fixed but if i can't figure it out i don't have any choice