Help ID this wire

[csanch40]

Was under the hood to check oil on my 04 XLT 5.4 2v and noticed this wire disconnected from under the engine cover, I can trace the wire to the terminal behind the battery (see photos)

Any help here would be great. I do have the Dorman after market intake manifold. Perhaps it’s not compatible? It was installed years ago. (I was on a budget).

 

[Hamfisted]

Pan out so we can see more of the engine bay. But that looks like the vacuum line off your hot water control valve there in the heater hose above the passenger side valve cover area.










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