Abstract: A method for controlling engagement of an automatic transmission in response to manual operation of a gear shift lever by the vehicle operator includes determining the instantaneous position of the PRNDL shift lever and checking whether that position has changed since the last execution of the control algorithm. Next the method determines whether the gear shift lever has moved from the neutral position to the drive position or whether it is moved from the drive position to the neutral position since the last execution of the program. In response to these checks, various flags are set and an engagement timer is loaded to a predetermined period. Finally the method passes the shift lever position to a microprocessor depending on the state of the flags, expiration of the timer and the vehicle speed or turbine speed.