If you look like bolland said to the left of the connector there is a water pump, place your finger on it and see if you can feel it when you hear the buzzing.
Also I wouldnt keep disconnecting that connector with the ignition on as you may knacker the ECU with a power spike.
Your car hasnt got the coil which is what overseer suggests as as you can clearly from your pic the HT leads coming from the coil pack.