EMB ERJ 170/175 ER/LR
Flight Crew Air Transport Pilot (ATP)
Time Pressure; Troubleshooting; Workload; Distraction; Confusion
Aircraft Equipment Problem Less Severe
Air Traffic Control Issued New Clearance; Flight Crew Overcame Equipment Problem; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Diverted; Flight Crew Landed in Emergency Condition
Aircraft
While enroute at FL340 and a bugged Mach number of .70M; the captain noticed a 'LIM' (Limited Thrust) appear on the FMA (Flight Mode Annunciation) panel on the PFD and our actual speed showing .72M. The number 2 engine indicated an N1 value of approximately 97% and the number 1 engine indicated an N1 value of approximately 70%. We disconnected the auto throttles and tried to manually reduce engine thrust on the number 2 engine but it was unresponsive. We discussed the situation and came to the conclusion that the number 2 engine was uncontrollable. We decided to contact dispatch and maintenance control. We were given possible alternates; diverted; and [advised ATC]. We shut down the number 2 engine per the QRH engine shutdown procedure and began a controlled descent while managing and balancing the fuel load. In order to get a second generator online; we started the APU at FL325. While balancing the fuel; we received FUEL LO LEVEL EICAS warning messages. We were actively monitoring the fuel load and knew we had 6000-7000 pounds remaining and we were balanced within limits. The messages cleared on their own while we were managing the fuel. We performed the QRH One Engine Inoperative Approach and Landing procedure with appropriate performance numbers. We stopped on the runway; communicated with ARFF (Aircraft Rescue Fire Fighting); ATC; passengers and flight attendants. We taxied to the gate and deplaned passengers. We then wrote up the engine malfunction and APU start limitation exceedance. We looked at the QRH procedure for the FUEL LO LEVEL warning messages and agreed they were associated with the state of the aircraft having one engine inoperative. I am unaware of the cause of the event. I suggest presenting this information to the airplane manufacturer and the engine manufacturer. I also recommend presenting the information to flight crews during recurrent training. This could be done with emphasis being placed on receiving a FUEL LO LEVEL warning message with plenty of fuel in the tanks. I would suggest that the APU start limitations be placed next to the instructions to start the APU during the QRH procedure. I would also suggest a possible note in the QRH with the Engine Shutdown procedure that you may receive FUEL LO LEVEL warning messages while balancing and managing fuel.
[Report narrative contained no additional information.]
An Embraer ERJ-175 flight crew reported difficulty controlling the thrust of the #2 engine. Using appropriate emergency checklists; the engine was secured; and the flight successfully diverted to a suitable airport.