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(website host) for help on 86-95 5.0 Mustang wiring Mustang FAQ - Engine Information Everyone should bookmark this site.
Vacuum Diagram 87-93 Mustangs
The diagram says 88 Mustang, but except for the vacuum line connected to the MAP/Baro sensor, it is the same for all 5.0 Mustangs from 87-93. The 89-93 Mustangs vent the MAP/Baro sensor to open air. http://www.veryuseful.com/mustang/tech/engine/images/88Stang5.0Vacuum.gif