Depends on a lot of factors. I assume the faceplant was right at the wake when you hit it. What kind of boat? Inboard? Inboard/outboard? How long was the rope? What were the water conditions?
In general when you add 600-700lbs. of water to any boat you can certainly change the wake significantly (some boats more than others). Could be that adding that weight in the back of the boat made the wake start curling or mushy at the length that you hit it. If you don't have a good edge going through that type of wake you can easily take water over the top of the board (especially in rougher water) which is pretty much a guaranteed faceplant whenever that happens.
Otherwise it caused by the "relative sack size" problem-- bigger wake means you need bigger balls to charge it and go big. Without those you might just be flattening out at the last second on the bigger wake and digging the board or taking water over it.
Hope that helps