Functional stability and in-vivo reliability are significant factors determining the longevity of a neural interface. In this ongoing study, we test the performance of a wireless floating microelectrode array (WFMA) over a period of 143 days. The topography of the microelectrodes has allowed for selective stimulation of different fascicles of the rat sciatic nerve. We confirmed that motor evoked thresholds remain stable over time and that the nerve stimulation charges were within tissue safety limits. Importantly, motor evoked responses were elicited at threshold currents in fully awake animals without causing pain or discomfort. These data validate the use of the WFMA system for intraneural interfacing of peripheral nerves for neuroprosthetic and bioelectronics medical applications.