Is an infection engine cleaning a necessity?

Hello, no workshop manuals from Ford nor maintenance guides will ever say to perform a fuel induction service. So - since it is not expressly listed as a required service - the answer is no - it's not a necessity. However, when performed properly, a fuel induction service may provide an incremental benefit by introducing cleaner through a vacuum line in the engine into the combustion chamber. This can work to clean deposits that build up on valves in the cylinder head. The cleaner will impact these components and could prevent engine performance issues in the future. However, I would also counter that by saying that I personally feel that induction service has more value with newer vehicles that have direct fuel injection - which your Explorer does not. DI turbocharged engines tend to have build up on valves that induction services can help reduce and manage. So, in the end - an induction service isn't a bad thing, but it's not required, and it's benefits may be limited compared to the cost incurred.