As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ORD - CREW ADVISED, UNABLE TO FEED FUEL FROM THE LEFT TANK. THE CAPTAIN WAS CONNECTED TO TULSA TECH. NO SOLUTION WAS FOUND FOR THE PROBLEM. THE FLIGHT RETURNED TO ORD AND LANDED ORD WITHOUT INCIDENT. REPLACED CENTER FUEL BOOST PUMPS. SYSTEM GROUND CHECK NORMAL OPERATION.