With all the 3-passage torque converter, two passages are used for transmission oil (ATF) circulation with the torque converter and for clutch cooling, whilst the third passage is used independently to regulate the lock and unlock on the clutch. If the torque converter is faulty, it would build unexpected pressures https://torque-converter-clutch75296.ampedpages.com/helping-the-others-realize-the-advantages-of-torque-converter-clutch-60952472