On 28 August 1914, "E4" was one of eight submarines that took part in a raid against the German Heligoland Bight patrol by the Harwich Force. Three submarines were deployed as bait, with orders to try and get spotted by the German outer screen in order to draw German torpedo boat patrols into the clutches of British destroyers and light cruisers. Meanwhile, "E4", together with "E9" and were to patrol close to Helgoland. "E4" spotted the German torpedo boat being chased by British destroyers but could not get into a position to attack before "V187" was sunk by the British destroyers. Shortly afterwards, the German cruiser arrived, forcing the British destroyers to disperse, and although "E4" attempted to attack "Stettin", the submarine could not get into a good attack position before "Stettin" left. A little later, "E4" surfaced and picked up the crew of two boats from the destroyer , which were rescuing survivors from "V187" when the arrival of "Stettin" caused the boats to be left behind. "E4", short of space, also picked up three German survivors, leaving the remainder in a boat with provisions and a compass. On 10 September, "E4" took part in another raid by the Harwich Force, supported by the Grand Fleet against German forces in the Helgoland Bight. While the British surface forces found nothing, the submarines were more busy, with "E4" encountering the German submarines and . "E-4" attempted to torpedo the German submarines, but both her torpedoes missed.