You should not be moving it fast enough by hand to get that kind of feedback even if it is disconnected.
You can wire them in series or parallel.
What happens when it is plugged in and you try to move it?
parallel for those would be black (a) and green(c) on both motors to the first two pins on the ramps port, and then red(b) from one and blue(d) from the other to the third pin, then the two that are left to the fourth pin.
series is in this order ramps pin1-stepper1 a, stepper1 c-stepper 2 a, stepper 2 c to ramps pin2. understand what is happening here you can follow the current from the ramps board through both coils back to the ramps board. Then ramps pin 3-stepper 1 b, stepper1 d-stepper 2d, stepper 2 b-ramps pin4.