Your setup must be different than mine, my 4x4 vacuum line originates on the passenger side the the intake manifold and has nothing to do with the fuel pressure, and yes you would probably get a code.
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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