Well, it turned out it was not the sending unit afterall. Check the ohmage and I did see it change. I attached a pot to the plug and adjusted the pot and saw the gauge from full to 3/4 smoothly then it just poped to empty and jump back and forth to 3/4..
That lead me to suspect it is the gauge.. Now I will try to attach another ground wire to the cluster and see if that help..

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Tony S....
98 MB E320
85 MB 380SL
01 Subraru Impreza (sold)
04 Toyota Highlander
82 25' W/A Cruisers