You will need the three wire version. This version, installed on later model Porsches, has one wire for the signal voltage to the DME, and the other two provide a DC voltage for an internal heater in the Oxygen Sensor. The heater enables the Sensor to come up to operational temperature near immediately. The one wire Sensor does not have a heater, and the Sensor is out of the DME loop until the exhaust heats the Sensor to operational temperature. Go to Clarks Garage site at the following link to learn all you need to know about the Oxygen Sensor [
http://clarks-garage.com/shop-manual/fuel-18.htm]