Flashing engine light and loss of power after sustained speed over 70?

Hello, Dave here, contributing to RepairPal and providing expert advice since 2010. Conveniently, I am also the operating director of a Honda service department currently. I can tell you that your concern isn't terribly common. However, my first question is: what trim model Pilot do you have? LX, EX and EX-L models will be equipped with the 6 speed automatic transmission. Touring and Elite models will feature the 9 speed automatic transmission. It makes a difference for this question. Secondly - a flashing check engine light is almost always indicative of an engine misfire. This would set diagnostic trouble codes in the engine's processor and should be easy to for a service department to retrieve and evaluate. Are you aware of any codes read during the inspections? It may take some extended driving and monitoring to determine what's going on. Don't give up! Work with the service manager of your dealership to work towards a solution.