Normally if you diff plug was screwed in too far, the locker will remain locked but since it comes on/off on its own, it sounds like a piece from the spider gears broke off and is jamming the locker on and off. Were there any chunks in the diff fluid?
I sit on the fence and watch.
DD- 2010 Jetta TDI ~45-47mpg, 60k miles and counting.
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