Hello. Today I was parking my car, was little space, so I needed longer time to do that, after I've put into reverse maybe 5th time, I heard strange sound and started like vibrating the gearbox, or something like that, I tried 2 times more and on 3rd was not doing again. It's very first time it happend. What u think about that? Thank you. Margaret
The Megane is known for its rattling at times and the most common cause is the serpentine belt auto tensioner. It would emt the noise now and then and also at times after engine rpm drops when throttle is closed.
If the noise is no more present, then you have nothing to worry about but a check of the serpentine belt and auto tensioner is advised. Ensure the belt is in good condition.