Electrical Cranks ok but no start help

rocksolid

Member
Jan 24, 2019
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32
Dayton, OH
Hey dudes. After going through the checklist for my warm start issue I found a leak at my header which I think was giving me oxygen sensor problems. After changing my headers, I don’t know if it was me or my buddy helping me, but somehow the wire to the starter became loose and I think it grounded out. My starter solenoid started smoking and wouldn’t work. I replaced it, and now the car cranks fine but I have no fuel pressure.

As per Jrichker’s cranks ok but no start checklist, I have found that my fusible links are ok. I do not have 12 volts at the red fuel injector wire, which led me to believe its the ignition switch... but I do have 12 volts at the red and green wires on the ignition coil, which I think it supposed to mean my ignition coil is ok. Am I reading the checklist correctly? And if so, where should I go from here?

I also have no 12 volts at the pink wire on the fuel pump relay. I swapped that out and the computer relay just for good measure.
 
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rocksolid

Member
Jan 24, 2019
20
3
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32
Dayton, OH
If I'm getting 12 volts on both sides of the fusible links, that certainly means they are fine, right? Someone said in another thread that they could still be bad. I didn't quite understand it.
 

jrichker

StangNet's favorite TOOL
SN Certified Technician
Mar 10, 2000
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lowendmac.com
If you have an electrical problem, please include the model year of your Mustang. The electrical wiring scheme changed at least 4 times in 79-93 Mustangs.
 

rocksolid

Member
Jan 24, 2019
20
3
13
32
Dayton, OH
It’s a 1988 LX 5.0 with mass air added if that helps at all. I’ve been testing the wires for 3 days, and short of ripping all the wires out and re doing them, I’m not sure what else to do. Very sad and frustrating. Hahaha
 

jrichker

StangNet's favorite TOOL
SN Certified Technician
Mar 10, 2000
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Dublin GA
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It’s a 1988 LX 5.0 with mass air added if that helps at all. I’ve been testing the wires for 3 days, and short of ripping all the wires out and re doing them, I’m not sure what else to do. Very sad and frustrating. Hahaha

The following are diagrams courtesy of Tmoss & Stang&2birds

Complete computer, actuator & sensor wiring diagram for 88-90 Mass Air Mustangs
88-91_5.0_EEC_Wiring_Diagram.gif


5.0 wiring diagram for Fuel Injectors, Sensors, and Actuators
fuel-alt-links-ign-ac.gif


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.


TFI module wiring for 94-95 Mustang GT
http://www.veryuseful.com/mustang/tech/engine/images/Mustang-94-95-IgnitionControlModule.gif

Complete computer, actuator & sensor wiring diagram for 94-95 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/94-95_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 88-90 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

5.0 wiring diagram for Fuel Injectors, Sensors, and Actuators
http://www.veryuseful.com/mustang/tech/engine/images/mustangEngineHarness.gif

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

O2 sensor wiring harness
http://www.veryuseful.com/mustang/tech/engine/images/mustangO2Harness.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 & pin out
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

Mustang 5.0 Lights and Radio schematic, by TMoss:
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxLights-Radio_diag.gif

87-92 power window wiring
http://www.veryuseful.com/mustang/tech/engine/images/mustang87-92 PowerWindowWiring.gif

93 power window wiring
http://www.veryuseful.com/mustang/tech/engine/images/mustang93PowerWindows.gif

T5 Cutaway showing T5 internal parts
http://www.veryuseful.com/mustang/tech/engine/images/5_Speed_Cutaway_Illustrated.jpg

Visual comparison of the Ford Fuel Injectors, picture by TMoss:
http://www.veryuseful.com/mustang/tech/engine/images/Ford_Injector_Guide.jpg

Convertible top motor wiring http://www.veryuseful.com/mustang/tech/engine/images/mustang88VertTopMotorCkt.gif

Engine mounted fuel injector harness
http://www.veryuseful.com/mustang/tech/engine/images/mustangEngineHarness.gif

Location of the TPS, IAB, and the 10-pin connectors on a 5.0, picture by TMoss:
http://www.veryuseful.com/mustang/tech/engine/images/TPS_IAB_Pic.jpg

Starter circuit
http://forums.stangnet.com/attachment.php?attachmentid=21328&d=1080916057

Alternator diagram for 94-95 Mustangs.
http://www.veryuseful.com/mustang/tech/engine/images/Mustang-94-95-Alt.gif
 

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