When the solenoid operates properly, the problem is most likely within the torque converter alone. If your solenoid will not let air to flow, put it within a clean up container of computerized transmission fluid and electrically cycle it to see if you can eliminate any blockage from the solenoid. https://torqueconverterclutch07383.pages10.com/what-does-torque-converter-clutch-mean-69585678