fusible link burning!

[crazy-ed-57]

i have a 92 mustang gt which was running fine until one day while driving the car just died. car will crank but not run. i dont hear fuel pump kicking on. after i got car towed home i found that the dark blue 20 gauge fusible line that connects to starter motor relay was burnt out. replaced with correct fusible link wire and when i turn on ignition the fusible link burns up again! awhile back i had a small fire in the engine compartment and i had to replace the tfi connector with a tfi pigtail. once replaced car has been running fine for a month until it died. have any idea whats causing fusible link to burn up? how do you trace down a short or a ground problem with a digital volt meter?

 

[jrichker]

Disconnect one item at a time on the sick circuit. When the overheating or blowing of fuses stop, you have found the problem.

I would start in the red wire circuits, looking for damaged wiring of obvious signs of overheating and damage. Standard 15 amp automotive fuses
can be substituted for the blue fuse link for troubleshooting purposes.

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/ Everyone should bookmark this site.

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

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

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

HVAC vacuum diagram
http://www.veryuseful.com/mustang/tech/engine/images/Mustang_AC_heat_vacuum_controls.gif

TFI module differences & pinout
http://www.veryuseful.com/mustang/tech/engine/images/TFI_5.0_comparison.gif

 

[crazy-ed-57]

i'll try that jrichker ...boy i hate electrical problems!

 

[corvetteguy]

You can go to the
back to the connector that feeds the
fuel pump and gauge.
Disconnect it and when your fuse link
is fixed you can measure 12 volt between the big
black and orange /blue wires.
You can ohm meter the opposite side of the
connector to see if the motor is shorted.


My fuel pump went two weeks ago, and
a buddies in tank pump went
out yesterday. An a
friends in tank pump went a few
weeks ago.
I wonder if there is a ADDITIVE in the gas
killing the pumps?

 

[crazy-ed-57]

installed a fuse holder with a 15 amp fuse so i could start tracking down short. i unhooked fuel injector harness and fuse didnt blow when i turned on ignition and fuel pump came on. ran out of time but i'll hook harness back up and unplug everything to see if fuse blows with just harness attached...if not then i'll start plugging things back in one at a time to see what makes the fuse blow

 

[865.0HO]

Unplug the alternator and try it again. I had an alternator fail a couple years back that created a dead short. Upluged the harness from the alternator and voila', the short dissappeared.

Try it, you never know.

 

[crazy-ed-57]

got to harness and unhooked everything...didnt blow fuse. then i started to plug things back in one at a time...still didnt blow fuse...what the heck! i'm still going to go thru injector harness to see if there is any cracked insulation on wires causing short.

 

[HISSIN50]

got to harness and unhooked everything...didnt blow fuse. then i started to plug things back in one at a time...still didnt blow fuse...what the heck! i'm still going to go thru injector harness to see if there is any cracked insulation on wires causing short.

Are you cycling the key after you replug each item back in?

 

[crazy-ed-57]

didnt think of that hissin50....maybe that will tell me something...i'd rather know for sure whats causing fuse to blow...don't want to get towed again!

 

[crazy-ed-57]

went thru injector harness and it looked ok...put new tape on everything, put it back on and it fired up...what the heck...i'd rather of known what was causing the problem. sure hope it doesnt leave me at the side of the road again! thanks for all the help guys!