Date: 201701
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Daylight
Aircraft: EMB ERJ 145 ER/LR
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Taxi
ATC / advisory: Ground ZZZ
Aircraft component: Engine Control
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: First Officer; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Anomaly: Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew
When detected: Taxi
Result: Flight Crew Returned To Gate
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: When taxiing in from the previous flight in Aircraft X; we got an E2 Idle Stp Fail EICAS advisory message. Upon parking at the gate; we called maintenance and wrote it up in the logbook. The mechanic reset the system and signed off the aircraft with 'ops checked good'. We pushed back from the gate to depart and upon starting engine 2; the message came back on the EICAS. The Captain called Maintenance. They instructed us to make a gate return. We communicated with Operations and followed through with the gate return as normal. ZZZ maintenance came out and put two MELs on the aircraft. 1. Idle stop solenoid 2. Thrust Reverser 2 (an associated MEL). So; the logbook was signed off and the dispatch release was updated. We pushed back from the gate for a second time. Upon starting Engine #2; the same EICAS message came back. (E2 Idle Stp Fail). The Captain and I referenced the MEL and there was no mention of an EICAS message that may appear associated with that MEL. (Usually this would be written in the logbook if it was an expected indication) So; the Captain called Maintenance Control again. And their response was that they had no idea if that message was normal. But; that we could 'start pulling circuit breakers if we wanted to.' This is not normal procedure for us so; we said no. We we're put on hold and when they picked up the phone again they still had no answer for us. So; we planned to make another gate return. We decided to use other resources at our disposal before returning to the gate. We called Maintenance in ZZZ and they sent a mechanic out to the window of the cockpit (this was a different mechanic than we had worked with the 2 previous calls) and we explained the situation. He said we were probably ok but did not give any source for that information or explanation. We reference our QRH which said; that if this EICAS message is present; 'Never set thrust below idle inflight.' We called the Chief Pilot in ZZZ; both assistant chiefs at ZZZ1; ZZZ2; chief pilot on call; none of them answered. We couldn't get a straight answer from anybody. So; we returned to the gate for the second time. We felt this was a safety of flight issue and without an answer; we didn't feel comfortable taking the aircraft. The mechanic that met the aircraft said that some aircraft will get that message but some will not normally get it. (We hadn't seen him before so he was the third ZZZ mechanic to work with us.) The ZZZ chief and assistant Chief arrived at the aircraft and said that they spoke to their head mechanic in ZZZ and that he said that the message would be normal under these conditions on aircraft that had a certain software update. But; the aircraft that didn't have that software update this would not be normally associated with the MEL. We took the aircraft and completed the flight. There were many threats in this situation. As a crew; I feel the CA and I handled this well and were on the same page. However; the inconsistency of the answers we were getting from the many mechanics in ZZZ and maintenance control was a big threat. They were more concerned with telling us anything we wanted to hear to get us to continue the flight rather than being concerned with safety and making sure the situation was handled correctly. This situation makes me distrust our mechanics which also presents a problem for the future and us working together. I also feel; the MEL document's incomplete information was a threat. Usually; when a message may be presented while under an MEL; that message would be specifically outlined in the MEL itself. Here; it was missing. The company could make sure that the MEL document is updated to completely cover that this EICAS message would be normal. If that document had been clear; we wouldn't have had any issues continuing the flight. I also feel that the inconsistent answers we got from maintenance and maintenance control were very confusing and did not instill confidence in the fact that they know what they are doing or are concerned with the airworthiness of the aircraft rather than making things look good on paper.




Synopsis: EMB-145 First Officer reported an Engine Idle Stop Fail EICAS message on start up. Returned to the gate twice due to getting the same message even after MEL action. Crew eventually completed the flight.