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before, i never go full tank when i go get gas but last week i just topped it off and till now its somewhere still close to F. now, i took off the cluster and took off the connections behind it and saw the needle go down to empty and plugged it back in and goes up slowly and showing i have bout 3/4 left of gas. but when i go drive it again, it goes up close to F. just wondering if anyones had this prob? what could be causing this to happen?