I have a Legacy engine that does that also on this 6-12054 track section:
is that the one you are talking about?
The manual recommends using a separate power source (not track Power) when using TMCC or Legacy engines:
I haven't made the switch to another power source yet but I should.
Mark
I believe the manual recommends that ,because the operating track is designed for 10v-12v, not the 18v of a command control TMCC/legacy layout.
18v pushes the risk of overheating and damage to the operating track section when activated.
You could try giving the rails on this section a good cleaning. I have some locos that are more sensative to dirty track than others. The newest Legacy stuff seems to have the most issues on track that "appears" clean but really isn't.
Otherwise, the battery/capacitor might be your last resort.