If you have a PnP unit you need to specify if you're going to use something other than the stock PTC, it clearly says so when you order - or the person you bought it through should've asked or pointed it out since the stock PTC sucks but works adequately with the stock ECU and hot wire air mass measurement.
I always get a new NTC sensor (the open body from the web shop) and install it on a flange screwed into the stock position, or if there is a pressure pipe before the throttle body. On the stock motor there is only rubber before the throttle so the intake and stock location is the only real option.
