i have an 89 chevy blazer k5 tbi the fuel gauge stays way past full. i took the dash off to see if it was just stuck, i moved it to half way and when i started it up it went right back to past full, ive heard it could be a bad ground wire or bad sending unit, or bad gauge cluster. any help before i start taking the tank and pump out.??

 

bad ground came to mind. check the ground from the sending unit to the frame.

 

i have dropped the tank to check the pump and undid the ground but it was doing the same thing before and after i dropped it. unless its in the wire itself or bad connection on the sending unit side