This is not a Nissan specific code; http://www.obd-codes.com/p0442 It is probably your gas cap is loose.
Trouble code P0442 means: Evaporative emission control system, small leak detected
P0442 indicates a small leak in the evaporative emission control system. Most commonly a loose or leaking fuel cap.
Trouble code P0442 means: Evaporative Emission System Leak Detected (small leak)
Trouble code P0442 means: Evaporative Emission System Leak Detected (small leak)
P0442 Evaporative Emission Control System Leak Detected (small leak)
Trouble code P0442 means: Evaporative Emission System Leak Detected (small leak)
P0442 Code indicates Evaporative Emission System Leak detected (small leak). What are the causes? What components need to be repaired
P0442: Evaporative Emission System Leak Detected (small leak) P0455: EVAP Large Leak Detected
Evaporative Emission Control System Leak Detected (small leak) It is a very small leak in your EVAP control system. In fact it could be as small as 0.04' in in diameter.
Trouble code P0442 means: Evaporative Emission System Leak Detected (small leak)
Trouble code P0442 means:Evaporative emission control system leak detected (Small leak)
Trouble code P0442 means:Evaporative emission control system leak detected (Small leak)