THIS IS a 2005 Escalade

Hey so recently my gas gauge stopped being accurate, it was right after i topped the truck off, ive driven it about 2 weeks like that but took it apart today.

This video was done on a full tank, the gauge is working properly but i have noticed the issue..... when you turn the key off the gauge doesnt go back smoothly or something is holding it back as you will see below...

is that the gauge or a censor? Not sure what to do here, i wish i could fix it but not sure why it will not just go back but goes forward perfectly, again this is on a full tank.

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