I've got a NA S5 engine and a Haltech F10. Right now, the MAP sensor is plugged into the nipple at the back of the runner of the front rotor. I'd like to move it to the nipple just after the throttle body that reads the pressure of the intake plenum but I don't know which of the three is the correct one. I can tell from the FSM that one picks up before the throttle body, one between throttle plate sets and one is in the plenum but it's not clear which is which. Which nipple is it?

 

Multiple choice answer

1) Upper
2) Middle
3) Lower

 

I don't have a series five n'a, but if I had one, I'd just idle the car and pull one off at a time and see which is pulling vacuum FROM the metal nipple. I THINK on a series four, non turbo, at the front of the throttle body where there are three nipples, the one on the bottom is the one that is a source of vacuum.

 

Just in case anyone else want's to know, it's (3).