I just finished dead money dlc and got out with the gold bars. I used my big mountain transportalponder to port to the sink. i reapaired my items and was left with 4300 caps and vendor has over 34000. i tried selling my items
and they sell but i dont get my money and am glitched at 4300 still. Can someone please help or is there anyone else out there with the same glitch.

Can't say I've tried this, will do sometime soon though.
Only fix that comes to mind is reloading a save before the DLC started.

Are you able to purchase stuff over your 4300 cap limit?
If so it might just be a display issue on the shop UI - does it still only show 4300 caps on your pipboy when you leave the conversation with the Sink?

This problem was reported sometime in mid 2011 (maybe April). It's a bug with the sink computer getting stuck at 32k and 64k caps. Bethesda has not posted an update to this topic since August of 2011, and that was just noting that the bug still existed. Hopes are low that it will ever get fixed at this point.

If I am being too harsh, prove me wrong.