My Lionel 38020 Lionmaster PRR T-1 Duplex works fine in Legacy Mode except that chugging sounds and smoke shut off for a few seconds at a time and then restart. This even sounds realistic sometimes as prototype steam locomotives do this too. But it happens constantly every few seconds.
I already replaced the cherry switch and also the infrared sensor assembly and sensors between engine and tender but this did not solve it.
Any suggestion s would be helpful. Phil