As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: LEFT FUEL TANK READINGS ARE ERRATIC. IT SHOWS FUEL CONTENTS INCREASING AND DECREASING RAPIDLY CONTINUOUSLY. AFTER ONE HOUR OF RAPID INDICATION FLUCTUATIONS, THE LEFT FUEL GAUGE GAVE UP AND BLANKED OUT COMPLETELY. REMOVED AND REPLACED FUEL QUANTITY PROCESSOR UNIT. PER AMM 28-41-81. OPERATIONAL CHECK GOOD.