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Discussion Starter · #1 ·
Hi guys I’m checking all my cabling as a rat chewed some and I’m repairing it
I think I have it all good, but the injectors get 2 pulses when power is first turned on and none after that so it dosnt run. I’m looking at the coil wires . There are 3 wires ( I don’t have the external igniter) pin 3 power tick
Pin 2 tachometer tick
Pin 1 ingnighter trigger signal wire
Where do I connect this ?
13548
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Now it sounds like you know they connect to the coil.
1- is the coil pulse signal from the ECU (when to spark).
2- is that pulse signal (1) sent to the tachometer.
3- is the 12V + power the coil uses to fire the spark plugs.

This is where I get a bit confused. Where did the rat chew the harness and how much did he eat.
Wherever it is all 3 wires connect back to the same 3 wires, you say you found 2 the 3rd should be nearby.
Are you bypassing the factory wires? I wouldn't recommend doing so without a factory workshop wiring manual or removing the tape from the wiring harness and checking the path of all the wires you wish to replace automotive harnesses often have wires spliced in them if a signal is needed in two locations they will splice the signal at their closest points to save on wire.

So if for example you run #1-coil pulse signal from the ecu to the coil but the factory harness wire was T'd into another device, it will no longer get the signal it needs to operate.

You would be amazed by how many spliced or wires doubled at the connector running to other devices in factory wire harnesses.


Usually if the injectors won't fire it is one of the feedback signals going to the ECU, like Crank Position (CKP) Signal or Cylinder Identification (CID) Signal or G signal or NE1 or 2 crank signal...
The ECU pulses the injectors to start the engines and waits for a signal to Identify crank/cam position, without that signal it doesn't know what stroke or cylinder it's on and does not pulse the injectors.
These are Hall Sensor Signals, often they will share 1 ground wire for all of them, start by making sure there is ground at all the connectors (harness side) for these sensors. Then check for continuity between these sensors pinouts and the ECU pinouts.
Just search for the same colored wire in the same gauge at the ECU harness plugs.
 

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Discussion Starter · #3 ·
Now it sounds like you know they connect to the coil.
1- is the coil pulse signal from the ECU (when to spark).
2- is that pulse signal (1) sent to the tachometer.
3- is the 12V + power the coil uses to fire the spark plugs.

This is where I get a bit confused. Where did the rat chew the harness and how much did he eat.
Wherever it is all 3 wires connect back to the same 3 wires, you say you found 2 the 3rd should be nearby.
Are you bypassing the factory wires? I wouldn't recommend doing so without a factory workshop wiring manual or removing the tape from the wiring harness and checking the path of all the wires you wish to replace automotive harnesses often have wires spliced in them if a signal is needed in two locations they will splice the signal at their closest points to save on wire.

So if for example you run #1-coil pulse signal from the ecu to the coil but the factory harness wire was T'd into another device, it will no longer get the signal it needs to operate.

You would be amazed by how many spliced or wires doubled at the connector running to other devices in factory wire harnesses.


Usually if the injectors won't fire it is one of the feedback signals going to the ECU, like Crank Position (CKP) Signal or Cylinder Identification (CID) Signal or G signal or NE1 or 2 crank signal...
The ECU pulses the injectors to start the engines and waits for a signal to Identify crank/cam position, without that signal it doesn't know what stroke or cylinder it's on and does not pulse the injectors.
These are Hall Sensor Signals, often they will share 1 ground wire for all of them, start by making sure there is ground at all the connectors (harness side) for these sensors. Then check for continuity between these sensors pinouts and the ECU pinouts.
Just search for the same colored wire in the same gauge at the ECU harness plugs.
Cool thanks,
I just can’t find what wire it splices to.
the coil trigger wire go’s to the ecu but on the ecu pin outs nothing says coil trigger unless it splices onto the distributor ignition wire or somewhere else
 
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