The CKF sensor is the Crank Speed Fluctuation Sensor and is located near the Crank pulley on the bottom of the engine on the driver's side. The wires come out from between the crank pulley and the alternator. From what I understand it only exists on OBD2 engines so I don't think you have it. Note that mine was not even connected for a while after my swap (B16A2) and my VTEC worked fine. If you're running the B16A3 (obd1) with a 96 GSR ECU (obd2) then you should probably think about getting the proper ecu to match the engine and save yourself alot of headaches.