Does your gear shifter make a metallic rattle noise or fail to return into the centre of neutral when you let go of it?
This is common to k11 micras and the solution is simple
I made a quick repair job to the gear-stick return spring. This also broke on my last micra. It's a pretty common fault, luckily its extremely easy to fix - took me about 20 minutes. Put the car up on the ramps, remove the exhaust heat shield that's in the way, and there you find the spring dangling by the end that didn't snap off. Simply bend a new hook out of the next end coil and slip it back in there. Now my gearstick returns into the middle nicely and doesn't rattle from the spring dangling around.