I have exactly the same problem on two Treks that had their engines replaced under warranty. Trek doesn't know the solution, nor does TQ, apparently. If anyone has managed to get a job after replacing the engine, I'd appreciate the solution.
Has anyone found a solution? Since I replaced the engine under warranty, I can't connect to the Trek app I've tried everything, and not even Trek knows how to fix it.
I don’t know what I can do to be able to connect.
I have tried it a little more and the conclusion is that it improves a lot but not 100%, the speed is still not constant but I repeat that at least it is usable, not like before when it was useless.
Trek has designed for the RAIL and POWERFLY a piece that modifies the position of the sensor with respect to the brake disc magnet, the little that I have tried finally works!!!