Hello:

When I'm cruising in 4th gear (overdrive), i notice that it doesn't take too much throttle input to make the convertor unlock and slip a few hundred RPMs.

Does the lock-up mechanism unlock naturally based on the torque load or does the transmission ECU take inputs from the TPS (throttle position sensor) to lock and unlock the convertor?

thanks

 

Both.

 

So if the TPS sensor input was taken out of the equation, how much torque could the lock-up mechanism handle?