it is not a nut as such, just the end of the throttle cable, which has a hexagonal shaped head.
anyway i got my mate to put his foot to the floor, while i got in the engine bay, i couldnt move the throttle anymore manually, so i guess if i did something to fix it, and i pushed my foot to the floor, it could stretch the cable too far.
ill get over it, the stall shudders every time i moved the car slowly got annoying, but ive become used to it.