MTH Premier N&W 4-8-4 J #611 Steam Locomotive - Item# 20-3132-1

Make sure it's clean and well lubricated.  Make sure that the stripes on the flywheel are clearly defined.  Make sure that the speed sensor is at the appropriate distance from the flywheel, and that all the wires on the sensor are in tact.  Make sure that all of the connectors are secure on the board.

Before you do anything, test it with a different TIU output channel. We have seen the exact same behavior when a TIU output is failing.

What version DCS are you using, and have you recently updated the TIU?

Joe,

The first thing to check would be the tether connection, on both the engine and the tender ends.

So far good advice. I started with the easy solutions first. I oiled the running gear & disconnected the tether & re-connected it. As of now it's running fine. If it shows up again, I'll switch it to another loop & test other engines on the questionable track.

Not sure if this could be contributing to the problem but my MTH Z4000 has a failing potentiometer. I set the voltage to the tracks & I need to re-adjust while the train is running. 

Updates to follow.

Thanks,

Joe