A vacuum problem would be easily fixed if repair manuals had vacuum diagrams the non-tech could read and understand. Every vacuum diagram I have been able to see shows vacuum lines leaving a "symbol" (unidentified) and going somewhere; also unidentified. Rarely do you find a diagram that discloses the differences in "ported" vacuum & "manifold" vacuum/nor, what they are to be used for. One needs to know "what" a symbol is and what it looks like to be able to identify it to follow the vacuum routing.