With all the 3-passage torque converter, two passages are employed for transmission oil (ATF) circulation through the torque converter and for clutch cooling, although the 3rd passage is employed independently to manage the lock and unlock on the clutch. Tough idling is an additional widespread symptom of a foul torque https://finnhpsuv.answerblogs.com/34467343/torque-converter-clutch-fundamentals-explained