Im not sure i know what your talking about when you say the vacuum line coming from behind the engine. On my setup i have one vacuum line that off the side of the intake and goes behind the battery to the solenoid. Then from there a line comes off and goes down toward the passenger wheel and splits, one end goes to the passenger wheel and the other goes along the cross member to the driver wheel. Maybe they changed the hose routing after early 04 like mine. But i would be careful what vacuum lines you start unplugging and plugging into. The one going to the solenoid on the fuel rail controls your fuel pressure. So if your tapping into that and starving your fuel pressure regulator for vacuum you might run your truck lean or rich depending on the situation. Just a thought.
2012 F-150 XLT 4x4 EcoBeast SuperCrew
2007 F-150 XLT 4x4 5.4 SuperCrew - Leveling Kit - Magnaflow Cat Back - Tonneau cover - Traded
2004 F-150 4x4 S-Cab, 4.6, Auto, Edge Programmer - Traded
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