Add or remove engines from the list of vehicles for purchase.
Cht: AllEngines (obsolete)
This will make it possible to purchase all engines and wagons available in the current climate, if they have been introduced already. Use this if you can't buy some engines because you forgot to turn on persistent engines.
Note that it will not make engines available, which have yet to be introduced. If you want to have those engines too, you need to use the Year cheat first. The AllVehicles cheat is only intended for games in which some of the engines have expired already, not for those where they aren't available yet.
Cht: RemoveEngines (obsolete)
As the name would imply, this cheat is the exact opposite to the above cheat. Namely, it removes all engines from the list of engines that can be bought, unless the engine is currently in use. In that respect, it behaves a lot like persistent engines, except that the engines are removed immediately and not only after they get too old. Train wagons are not affected.
Those engines that have yet to be introduced will be available at the time of their introduction, that is, the RemoveVehicles cheat does not affect an engine until it was available for purchasing.