EFI wiring help

[Eads74bronco]

5.0 is installed, will run but has a wiring issue. The EEC relay pulls in and voltage goes out to the red power wires when cranking and in run position but it will not start. To get it to start I have to take a jumper wire from the run/start (Green/red) wire to the EEC relay power going out to the red wires. It starts right up then but I have to remove the wire so it can be turned off by the key. Without the jumper it only shows 11-11.5 v going the red power wires when cranking over. If the battery is hooked up to a charger it will start without the jumper but the battery checks fine and turns the motor over quickly. Not sure whats going on, here's the connections I can think of sitting here without the bronco here.

Grey/yellow to run postion (back of key switch)
Red/Blue connected to red/blue of bronco harness at the solenoid
Fuel pump relay seems to work correctly (cant rem all the connections)
EEC black/orange- (hot) solenoid

Seems like there's is a voltage drop going to the power (red) wires on the harness. Has anyone else had this issue?

 

[brianstrange]

There's a red/green that gets 12v+ on run

Also, what year bronco / charging system? If you have a mechanical voltage regulator that can add voltage issues

 

[Eads74bronco]

Sorry I meant Red/Green for the Run/Start
I just wired up the mustang alt today and it works, after it's started i can pull the positive battery post off and it will stay running.

 

[Eads74bronco]

And the Bronco is a 72

 

[ransil]

pull the TFI connector measure pins 3 & 4 in start & run,
3= 12 volts start
4= 12 volts run