i have a hemi with the factory intake on it. What is the sensor for on the front of the intake box??? if i remove the box and dont plug it back it what will it do

 

I believe that would be your air intake temperature sensor. It's used to help control your injectors and spark timing. Other than throwing codes, your truck would probably run pretty poor after a while without it.

 

ok if i build an intake or get one off ebay, do i just drill a hole and insert that sensor in the hole or what do i do???

 

My intake off ebay had a spot to put it back in:

 

is that a true k&n or just one of those cheaper ones off ebay???? i like the looks of it, and does it have a good sound to it??

 

That's not a true K&N intake. The K&N doesn't have the silicone sections to join multiple tubes together. It's one piece from the throttle body to the filter and comes with a heat shield. Also, the plastic tubes have proven better performance figures.

The only sensor I know of should be attached into the tube, and that is your air intake temperature sensor. It needs to be in the tube or your truck will run like ****.