I was trying to find the Iat sensor on my honda prelude type s 92. I changed out my intake so I was wondering if I had to plug it back in but I dont see it.

 

U changed out your intake pipe and filter? Or you changed out your Intake Manifold?

The IAT sensor on every Honda I've ever seen was directly on top of the Intake manifold, either on the plenum or on one of the runners themselves...

And yes you wanna plug it in, cause you will throw a CEL if not... Although it will not really affect your performance, it is mostly to compensate with extra fuel for temp extremes, such as very cold or very hot... It's basically for driveability in cold and hot weather...