No power getting to coil

[bdydrpd88]

K heres the skinny got a 90 model LX originally a 4cyl coupe converted to a 5.0. Motor in the car is a carbureted points ignition type. Yesterday car was running fine and a friend of mine was trying to help me get the tach back working in the car when he said the coil sparked when i tried to fire it up. Well make long story short now the car attempts to crank up but it has no spark coming from the coil wire. checked the distributor cap and it has the positive wire coming from the coil going into it everything checks out fine but someone told me it could possibly be an ASD relay under the hood in the power distribution block but all that crap was taken out of my car that I can tell, there is a fuse block under the steering column but I havent had a chance to check those relays yet, im assuming im on the right track cuz the ASD relay should control the fuel pump and all that other crap at startup and i figured if it was something with the distributor then id least be getting some kinda fire going to the coil. Any ideas before I go insane lol?

 

[enyawix]

I would start simple. I would test for power at the ignition switch, than have the coil tested. the coil will have a primary and secondary resistance range.

 

[bdydrpd88]

yeah i kinda ran out of daylight when this crap happened so i gotta wait till in the morning but it seems to me to be a fuse related issue because after my friend said something about a spark shooting off the coil the car cranked once then it acted like it just died and then started cranking but just wasnt getting fire to the coil. i replaced the coil on the car and it still doesnt got any juice going to the coil and someone just told me to check the Auto shutdown relay but i dont see anything under the hood i believe the motor in my car came from a pre73 mustang its still got old points distributor on it but everything brand new on it i think my buddy shorted something out today on the coil and fried a relay or fuse somewhere i just gotta trace it down tomorrow when its light out, heck i even thought about switchin to a HEI setup see if that may knock out the problem

 

[jrichker]

Carb to EFI conversions often suffer from electrical problems. That's the nice version of my opinion. Since you aren't the one to do the conversion, I'll spare you from the usual negative comments about such work.

The following diagrams will help get you aimed in the right direction. See the other diagrams for more on what the original 5.0 wiring was supposed to look like.

Ignition switch wiring: Note that there is a fuse link in the red/green wire going to the ignition coil. I do not know the location of it, but if you make sparks and smoke, it is probably blown open. Use a DVM or test light to confirm power to the red/green wire on the ignition coil. Measure between the red/green wire and the negative terminal of the battery.
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 Mustang FAQ - Engine Information 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

Complete computer, actuator & sensor wiring diagram for 91-93 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/91-93_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for 94-95 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/94-95_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

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

AutoZone wiring diagrams

For 79-88 model Mustangs
http://www.autozone.com/shopping/repairGuide.htm?pageId=0900c1528004e28c

For 89-93 model Mustangs
http://www.autozone.com/shopping/repairGuide.htm?pageId=0900c15280069677

For 94-98 model Mustangs
http://www.autozone.com/shopping/repairGuide.htm?pageId=0900c152801f5e3b

For 1999-2005 model Mustangs
http://www.autozone.com/shopping/repairGuide.htm?pageId=0900c152801ef7d7