Lionel Amtrak 505 Locomotive Odd Behavior

What you are experiencing with Odysessy turned off is normal if you are running the cars on very tight curves, as they will create a lot of drag for the locomotive to overcome. Leaving Odyssey on will get rid of this behavior and lead to a much smoother experience overall

You may also want to check if the cars are dry on the points that need oil and also check if the curves you are using are rated for their minimum required radius

Thanks.  I will try with Odysessy turned on.  The curves are 72", so I really don't think that is the issue.  I'm not sure I could make a more gentler curve.  All cars were properly lubricated, prior to running them, so I'm not sure that lubrication is an issue, either, but it is worth re-checking.  It does not appear to be a curve or car issue though.  It's as if the locos just "shut off" for a couple of seconds, the come back on at the new throttle.

The reason for the engines stalling out on long curves with odyssey off is because they need more current to compensate for the extra drag, so you would need to gently throttle up to get more power to the motors. But with Odyssey on it will compensate for the motor stalling out from extra drag and increase the power automatically to them to prevent them from stalling out.

There's an RPM reader on one of the motors of each engine that will constantly monitor motor rotation and tell the motor board to increase the power if it senses a decrease in rotation speed. But also decrease power, if it senses the motor speed increasing. So it will maintain a constant speed, no matter the load.

72" radius curve more than sufficient for those passenger cars, I am guessing you are running the engines with the matching aluminum double decker passenger cars? Those will further increase the chance of stalling on curves, since they are significently heavier then post-war cars. Hence why your post-war stuff doesn't have the problems your Amtrak train has... Much lighter cars means a lot less weight for the engine(s) to pull and therefore less chance of the engine(s) stalling out.

Thanks for the detailed information.  I will try it with Odyssey turned on.  Tired of yanking the cars off of the track when it decides to "stall" briefly in a turn.