As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TAXI FOR TAKEOFF CREW EXPERIENCED HIGH (FLIGHT) IDLE ON THE L ENGINE. UNSUCCESFUL ATTEMPTS TO ADVANCE THROTTLE AND RETURN TO IDLE WAS ATTEMPTED TO BRING ENGINE BACK TO NORMAL GROUND IDLE. CREW RETURNED TO RAMP WHERE TECHNICIANS TROUBLESHOT THE ISSUE TO, AND REPLACED THE APPROACH IDLE SOLENOID VALVE.