[yetibone]

hearing a "wizz-clunk" is not unexpected when the TC shift motor rotates to change modes in the transfer case.

To fix the OBDII e-com problem, just replace the cigarette lighter fuse in the power distribution box under the hood. The orange wire at the OBD data port is the power wire, fed by the same circuit as the lighter.

Sounds like the shift motor might have been between AWD/4WD, and 2WD.

EDIT: You might need to find somebody with a Tech2 scan tool to access trouble codes for the automatic transfer case.