4L60-E PWM Power Valve Problem Solver The 4L60-E PWM. Power-Valve is designed to help supply more converter charge oil to the fill circuit when the unit is in lock-up. This valve does not change lock-up operation but does supply more oil to an already over extended circuit. This valve can be use in any 4L60-E (PWM) unit 1995 and up but is extremely beneficial with 98 through 2001 units EC3 computer strategy.* This problem solver package works to eliminate the 1870 code problem in most applications* No valve body boring tools needed