Do the following. After programming the engines to the TMCC ID you want. Do the restore feature setting. That is engine # then AUX-1 then the number 8. This is done in the program mode. After entering number 8, slide your program switch back to run. I have worked on a good number of these engines in the past years. They are good runners. Many get sold (dumped) because of erratic running. I found the Achille's heel that causes that. Near the bottom of the smoke unit is a board that has plugs from each truck plug into. Plugs go out to any item that needs to see track power. If you see or have an engine with the running situation, look for this. Unscrew the board and flip it over. You will see some traces that have flaked off the board. Follow where the traces go and hard wire the path doing away with the bad traces. After doing that, I take a small artist paint brush and brush super glue over the flaked traces so they will not lift any more and find something they should not find. With these small boards hard wired, you have a good solid platform to work with.
Before MTH did the set of Demo FM engines, the Lionel set was very hard to find and very pricey. About six years ago, I was handed a set a customer purchased on fleabay knowing they did not run. Cosmetically they were perfect. The man told me to make them right and he did not care how much it cost. He had the situation I described above. He got out very cheap and was very happy.
Three years ago I picked up a set at York NIB for decent money. If you get a shot at a set, you will do OK.
