Section 159 (Vacuum Diagrams): Instructions
WARNING: This page is about a different car, the 1995 Ford Aerostar. However, it is still accessible from the selected car via links, so may be relevant.
Engine calibration number can be found on Emission Calibration Label located on driver's door or "B" pillar. See Fig 1. Using calibration number and appropriate VACUUM DIAGRAM INDEX, determine which vacuum diagram applies to vehicle in question.