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Yes, I have the wiring diagram.





The coils have 12v switched power, and the negatives from each coil goes to the ignitor. The haltech ignition outputs also connect to the ignitor. I tested each coil and they are getting power. There is a home and trigger signal going to the haltech.
Your ignitor is basically a power transistor unit, the 6G75 coils have transistors build right in the coils so there no need to use the ignitor unit. So wire the coils ecu signal directly from the ecu.
 

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Discussion Starter #42
Your ignitor is basically a power transistor unit, the 6G75 coils have transistors build right in the coils so there no need to use the ignitor unit. So wire the coils ecu signal directly from the ecu.
I originally had the coils wired directly to the ecu, still there wasn't spark. The only difference then was that I did not have distributor installed to act as the cam sensor. Are you sure that the 6g75 coils have built-in ignitors? Every coil I have seen that had built in ignitors seemed to be much larger.
 

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I originally had the coils wired directly to the ecu, still there wasn't spark. The only difference then was that I did not have distributor installed to act as the cam sensor. Are you sure that the 6g75 coils have built-in ignitors? Every coil I have seen that had built in ignitors seemed to be much larger.
Yes, it is shown in the diagram you posted.
 

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Discussion Starter #44
Big update.

The engine finally fired. I'll give alot of credit to Mysticj for making really look harder and brush back up on my electronic diagram reading skills. I was getting advice from several other sources saying that the coils didn't have built in ignitors (which they do) and I wired in a separate Haltech ignitor, which was wrong. The engine would have fired on my first attempt, when I originally wired the coils directly to the Haltech, but I found out that the ignition drivers in my Haltech were fried. Once those were fixed and the coils were re-wired how I had them initially, the engine fired.

The idle is very rough. I'm going to have my injectors checked, to make sure there isn't an issue since my car has been sitting for an extended period of time.

My tach isn't working. I'm not sure why, I'll check fuses, but my next task will be to figure out how the tach receives its signal. While the injectors are getting checked, I'll button up some of the loose ends of the swap. Maybe I'll get it running well enough to drive it for a week!
 

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The tach receives a signal from a white wire coming off the distributor. When the factory coil is grounded the white wire carries a kick back signal to the ECU which drives the tach. Since you don't have that you won't be able to run the stock one, you'll have to go external.
 

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Discussion Starter #46
The tach receives a signal from a white wire coming off the distributor. When the factory coil is grounded the white wire carries a kick back signal to the ECU which drives the tach. Since you don't have that you won't be able to run the stock one, you'll have to go external.
I am running the stock distributor. I am using it as the home signal for the Haltech. The stock distbritor harness is still being used.
 

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Yes but the kickback signal comes from the negative side of the stock coil which you are not firing since you have the haltech running individual coils. If you are not running the stock coil inside the distributor you can not run the stock tach.
 

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Discussion Starter #48
Yes but the kickback signal comes from the negative side of the stock coil which you are not firing since you have the haltech running individual coils. If you are not running the stock coil inside the distributor you can not run the stock tach.
Hmm, I wonder if there is a way to bring the signal from the coils to the stock harness.
 

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The problem is the wire sees a signal for each cylinder, individual coils can't be wired to ground the same wire without compromising them indefinitely. What you could do if you don't want an external tach is wire up a hall effect sensor and a six pulse reluctor on the crank pulley.
 

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Discussion Starter #50
The problem is the wire sees a signal for each cylinder, individual coils can't be wired to ground the same wire without compromising them indefinitely. What you could do if you don't want an external tach is wire up a hall effect sensor and a six pulse reluctor on the crank pulley.

I'm my research to find a external tach to install, I came across the auto meter tach adapter. Apparently it can be wired in the C.O.P. system and would be needed to run a auto meter gauge, but I then found that skyy406 installed the tach adapter to his avenger's stock tach to make it work.

I also sent an email to autometer asking if the tach adapter could work with the C.O.P. system and they said it would work, but they were not sure what signal my stock tach wanted to see, but they did say the autometer tach adapter, "will output a 12v square wave signal."
 

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The stock tach wants a pulse every time a cylinder lights so you'd need 3 pulses per revolution.
I think there is a difference between the 3G tachs when receiving ignition pulses such as the distributor coil fired once for all six cylinders and while the I4 tach takes in account of two coils firing...idk...not thinking clear...boring day at day. Has anyone swap an I4 instrument cluster in a GT or vice versa?
 

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No they're incompatible for a number of reasons.

But yes, the 6 cylinder tachs get 3 pulses per revolution, one every time the coil fires (which is 3 per rev of course). As for the four cylinders I'm not sure if they get a kick back signal or what since they've got two coils.
 

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No they're incompatible for a number of reasons.

But yes, the 6 cylinder tachs get 3 pulses per revolution, one every time the coil fires (which is 3 per rev of course). As for the four cylinders I'm not sure if they get a kick back signal or what since they've got two coils.
yea the ecu and dash receive their tach signal from the power transistor whenever the coil is firing, a drop/dip of power when the coil is firing is use for calculating RPM. In your case, you cannot tap into the coil for the transistor to get a RPM reference....so...like the 4G64, 4G93/4, Evo, Sonata/Optima & XG350, you must use a thing call an Ignition Failure Sensor or Misfire Sensor or what I like to call it: a Tach Reference Sensor to 'capture' the coil firing. Its a four pin sensor: Ign 12V, coil 12V, GND & tach output. The Ign 12V comes from the ignition SW, Coil 12V goes to the coils, GND is connect to all the coil GND, tach goes to the ecu & dash.
 

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I'm confused, I run the MSD setup where the white tach wire is used to trigger the MSD unit. Therefore there is no kickback to the ECU to give it an RPM readout, but I can still log RPMs with Evoscan just fine.
 

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I'm confused, I run the MSD setup where the white tach wire is used to trigger the MSD unit. Therefore there is no kickback to the ECU to give it an RPM readout, but I can still log RPMs with Evoscan just fine.
crank sensor is use to determine RPM in the ecu while the tach signal is use to confirm proper timing of ignition firing, if not, the ecu toss out a random misfire code.
 

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Ah then we are in accord. This is why I have P0300 indefinitely.
so msd gray wire doesnt work? u are running a cdi system which the msd unit stores ignition charge while the stock setup steps up the voltage via transistor. with the stock ignition, the ecu fires a ground signal to the transistor before reaching the coil. the other part of the transistor sends a voltage drop or signal back to ecu/tachometer...its easier to explain with a diagram.
 

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Yes the white signal wire that sends the tach signal to the ECU every time the power transistor is grounded wires into the white signal wire on my MSD box and tells that when to fire the external coil. I still have the distributor, I'm just using the external MSD coil because it's strong enough to do what I require from it.
 
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