Need some help please

Diagram courtesy of Tmoss & Stang&2birds


See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel pump, alternator, ignition & A/C wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Computer, actuator & sensor wiring
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Fuse panel layout
http://www.veryuseful.com/mustang/tech/engine/images/MustangFuseBox.gif

Vacuum routing
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

First you have a bad solenoid that's why the starter won't quit.

In your "jumping" testing phase you melted something. Look at your fusible links and the battery cables themselves with an ohmeter for continuity to prove them out. If you put the jumper cables on backwards even for a second you probably fried at least a couple things like the alternator and possibly the computer?

You might get off easy? Look for elephants. Main power supply wiring for sure. It's actually a "good" thing you have no lights that come right off the battery ahead of the ignition.