GMC JIMMY INSTRUMENT CLUSTER GAUGES FUEL LEVEL

I Wasn't Sure What Category To Pick. I Have A 2000 Gmc Jimmy, My Gas Gauge Is Not Reading Proprely, I Can Put 15gals And It Will Read...

Hi, My Motor Was Just Replaced With A Used Motor But Now My Gas Gauge Will Not Work. The Needle Stays On Empty And The Low Fuel Light Stays...

When I Turn The Key To The Ignition, The Needle Jumps Back/forth Very Rapidly. It Then Settles Down To The Correct Level In The Tank.