Again, reseting a PS1 engine t factory defaults using a Z4000 is simple.
First again, check the engine to ensure the battery is charged and working. This is powering the engine, waiting at least 30-60 seconds while the engine sounds start, and then dropping power. The sounds must continue after power is turned off to the track.
Then, with power off to the track (both handles fully down on the Z4000, then hit program (black button) on the channel to enter program mode. The use the up (white) and down (red) arrow key to increment up to 18 on the display. Then press select (yellow) and the track will power up. The engine will begin making sounds, then about 20 seconds later, the Z4000 will begin rapidly raising and lowering voltages to the track to program the engine and the engine should be responding with woosh sounds and then at the end 3 dings, and 3 dongs. As long as you hear 3 dings and 3 dongs, then press the program button (black) again, to exit program mode. The engine will shut down and wait until you hear the fart sound and then you can attempt to run the engine normally.
