"Wahoo" arrived at Pearl Harbor on 21 May 1943. The next day, Admiral Chester W. Nimitz, the CINCPAC, came on board and presented awards. Two days later, the submarine departed for the Mare Island Navy Yard, where she arrived 29 May to commence overhaul. From 11–20 July, the submarine underwent intensive post-repair trials and training. On 20 July, squadron commander Captain John B. Griggs, Jr., came aboard and presented more awards. On the following day, "Wahoo" departed for Pearl Harbor, furnishing services for surface and air forces while "en route". She arrived at Hawaii on 27 July 1943 and departed on 2 August for her patrol area. Four days later, "Wahoo" arrived at Midway Island, but she left on the same day.