Ive got this on mine, it has got a round shaped connector going to it, like the one that goes on the air charge temp sensor.On a previous engine change i had one of these that just had a stragiht through pipe with no connector so i dont think its a must for some ecu's? Mines a S2 but maybe this wasn't on the S1 if you have changed the inlet manifold aswell have a look on your old one c whats on that one.