No, Mike you dont need a sensor hole man. Are you getting CEL's? The best way to avoid Check Engine Lights for an Intake is to have it be free wtihin the engine bay. I set the intake up between the drivebelts and A/C lines, by placing the piping over the engine noise reduction cover. Oh course, you will want to use an Injen Hydro Sheild bag for that since there will be splashing water.
Injen Hydro Shield
I also have another intake that I have placed in the back near my brake fluid assembly for now. I will move that to my front bumper. However that will require a few steps: 1. Purchase of another Injen Hydro Shield, and just to be safe an AEM HYDROLOCK Stopper BKA' 3.0" bypass valve.
AEM - 3.0" Air Bypass Valve
2. Remove the Stock Air system completely; that will also require temporary Removal of the battery system (I already have that done and that process takes about 15-30 minutes of careful work.)
One intake is great for the 2006-2010 Accent, however 2 Intakes make it very dangerous.