What actually controls the converter and tells it to lock? I've posted before about my problem, but I still havn't figured it out. My converter will not lock when the tranny temperature is over 150 degrees. It locks and unlocks perfectly when it is under 150, but soon as it gets to it, it will not lock. I want to know what controls this locking. I've been told by a lot of people that I need to get it tuned, but I contacted Ion at madz28.com and he said that tuning wouldn't fix the problem because locking is not controlled by temperature. This converter is a Racing Edge 3800 Lock up which was taken out of my friends car who had no problems with it locking up, he had a 94 z28. I'm completly stumped as to what would allow it to lock up when its under that temperature, and then not lock as soon as it gets above it. Could my tranny be bad? Could the converter be bad, even though we just pulled it out of my friends car? Any help would be greatly appreciated!