Exhaust vacuum to intake?!?!

[david-b]

I was looking over at my exhaust (stock), because Im going to be installing my new exhasut soon (header, dp, cat conv, and cat-back). GOing from my CAI is a pipe that goes down, hits a sensor, and then attaches onto the stock downpipe. I remember when I first installed my CAI I bought some piping to redo the exisiting piping becuase it was too short. The open pipe sucks air in. The one that was there used to go onto the stock airbox.

Now, when I install the header, this whole piece will be eliminated. Will I get a CEL from not having the sensor? Or what can I do about that? Will I get any problems with removing it? Also, what exactly does that do?