3000 GT ignitor wiring for a standalone

X-man

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Wiring diagram to replace an MKIII ignitor with a Mitsubishi ignitor with an AEM or similiar plug and play unit.

VB - 12 volt positive
GND - Ground
IB1 - coil output #1 from AEM (factory iGt wire)
IB2 - coil output #2 from AEM (factory iGda wire)
IB3 - coil output #3 from AEM (factory iGdb wire)

OC1 - output to coils 1 - 6
OC2 - output to coils 2 - 5
OC3 - output to coils 3 - 4

The iGf wire is not used by the AEM and can be reasigned at the AEM connector to be a LS#1 through LS#12 output to drive the factory tach through an MSD tach adaptor part number 8920 which can be wired up right at the ignitor by using the reasigned iGf wire and the original Toyota tach feed from the stock MKIII ignitor.

Once this is all done you will need set some parameters in the AEM. Parameters such as turning coils 1,2,3, and 6,7,and 8 on, turning the multiplexing option off, and then setting the igntion phasing, spark teeth, and coil dwell.

Sean
 
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bfr1992t

The quiet one
Oct 29, 2005
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Great info! Can we build a list of recommended ignitors (car year/make/model/engine and part numbers)? Ideally also a list of connector parts to make this as plug and play as possible and coil dwell settings.
 

X-man

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You can use any 3 or up channel ignitor. The Stealth, Diamonte, and the 3000 GT all had this ignitor if it came with the DOHC engine. You will need the connectors from a doner car. If you use an ignitor with more channels you will just have to use correct input and output wires ie 300 ZX twin turbos use a 6 channel ignitor that you could tie the three input wires together( 1-6, 2-5, and 3-4) and have 6 seperate outputs if you were going to use 6 MKIV coils.

Advance Auto has 3000 GT ignitors for around 100.00 versus 350.00 to 400.00 for the MKIII ignitor.

You have tuneability with igniton phasing and you get rid of the multiplexing and I completely got rid of any and all misfiring issues with my car.
 

MRSUPRA

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Apr 11, 2005
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X-man gave me this info when I was having the low load/RPM misfire. Unfortunantly it only went away slightly on my car. I had to go with sequential injection to completely solve the problem.
 

TheNewRed

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Oct 19, 2007
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X-man;1294851 said:
You have tuneability with igniton phasing and you get rid of the multiplexing and I completely got rid of any and all misfiring issues with my car.

Ok so instead of using for example in AEMpro- the Multiplex coil option, you would use the Ignition Phasing option which gives you what kind of advantage? Can you not use phasing with the stock ignitor?
 

X-man

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TheNewRed;1295742 said:
Ok so instead of using for example in AEMpro- the Multiplex coil option, you would use the Ignition Phasing option which gives you what kind of advantage? Can you not use phasing with the stock ignitor?



The stock ignitor receives a signal for the location of number 1 cylinder then it takes care of when the rest of the firing order occurs, if I did my homework correctly. One of the problems seems to be if for any reason there is any interference via electrical noise or signal strength this can really disrupt the signal.

On another note going sequential on the injectors wiring and firing also made a huge difference in driveability. Basically you run the car like the parameters AEM has set up for a 2jz.
 

bfr1992t

The quiet one
Oct 29, 2005
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Close, the factory ECU sends an trigger signal (IGt) and combination of IGa and IGb to tell the ignitor which of the three channels to fire. The ignitor controls coil dwell, drives the tach (IG-), and signals the ECU when there is a misfire (IGf).

Switching injection from the AEM 7M default to semi sequential (like stock) has made a huge difference on all of the 7M cars I have tuned. Driveability, low end torque, and economy have all improved. I have not converted to sequential injection yet because of the 2800rpm ignition issue. I've researched several different ignitors and obtained transistors suitable for ignition duty to build my own. I just need to get off my lazy ass and get something done. Has anyone used the "#10 inj as coil" feature to run full sequential ignition? What coils are you using? Ideally COP, possibly with built in ignitors would be cool.
 

X-man

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bfr1992t;1296551 said:
Close, the factory ECU sends an trigger signal (IGt) and combination of IGa and IGb to tell the ignitor which of the three channels to fire. The ignitor controls coil dwell, drives the tach (IG-), and signals the ECU when there is a misfire (IGf).

Switching injection from the AEM 7M default to semi sequential (like stock) has made a huge difference on all of the 7M cars I have tuned. Driveability, low end torque, and economy have all improved. I have not converted to sequential injection yet because of the 2800rpm ignition issue. I've researched several different ignitors and obtained transistors suitable for ignition duty to build my own. I just need to get off my lazy ass and get something done. Has anyone used the "#10 inj as coil" feature to run full sequential ignition? What coils are you using? Ideally COP, possibly with built in ignitors would be cool.

Thanks for the more precise definition, I was trying to oversimply too much.

Here was what I sent to Matt for his 90 Supra, as mine is an 88.

Originally Posted by X-man
On the sequential injection hook up you are looking for plug C (the only 12 pin plug on the AEM). The numbers you want are on the bottom row on the left side of the connector.

10C is injector #7(which will go to injector #4 on the engine)
11C is injector #8(which will go to injector #5 on the engine)
12C is injector #9(which will go to injector #6 on the engine)

All the fuel injectors share a 12 volt supply wire from the injector resistor. The power wires will be colored:

Yellow for inj #1 and #4
Black for inj #2 and #6
Red for inj #3 and #5

The trigger wires for the ecu that you need to be concerned with are the:

White with a blue stripe for injector#4
White for injector #5
White with a red stripe for injector #6

You cut these wires out at the injector leaving about 3 to 4 inches off the injector plug to work with and attach the 3 to 4 inch pieces off the injector plugs to:

White/blue(inj #4) to pin 10C(inj #7)
White(inj #5) to pin 11C(inj #8)
White/red(inj #6) to pin 12C(inj #9)

On the pieces left sticking out of the original wiring harness I installed a red 18-22 ga butt connectors over the exposed ends to protect them.

You then have to turn off injectors number 4,5, and 6 and turn on/active injectors 7,8,9, and 10 and set them for primary under OPTIONS on the drop list. Then you go to FUEL, then ADVANCED FUEL, then INJ PHASING and set inject tooth #1 to 19.00, inject tooth #2 to 11.00, inject tooth #3 to 3.00, inject tooth #7 to 15.00, inject tooth #8 to 23.00, and inject tooth #9 to 7.00. Numbers 4,5,6, and 10 will have the number 0.00 in each of them.

Sean
 
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TheNewRed

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bfr1992t;1296551 said:
Close, the factory ECU sends an trigger signal (IGt) and combination of IGa and IGb to tell the ignitor which of the three channels to fire. The ignitor controls coil dwell, drives the tach (IG-), and signals the ECU when there is a misfire (IGf).
.
Either way, its still considered multiplexing(as sean stated). Im going to take your advice and use it Sean... These AEM's truely are brilliant!
 

bfr1992t

The quiet one
Oct 29, 2005
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TheNewRed;1296791 said:
Either way, its still considered multiplexing(as sean stated).

Uh-huh. I never said it wasn't.

TheNewRed;1296791 said:
These AEM's truely are brilliant!

After owning one for 5+ yrs, tuning many of them including staged injection with dual fuels, custom injection/ignition schemes, etc...I wouldn't go *that* far. The GEMS board is nice, the AEM adapter is ok, the software and resulting firmware code leaves a lot to be desired. It's decent for the price.

The reason why I described the factory setup in detail is to make a point. In PnP config the ignitor controls dwell, but with any other ignitor you will need to customize the coil dwell table. This is very important - you can destroy your coils quickly.
 

X-man

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bfr1992t;1296918 said:
Uh-huh. I never said it wasn't.



After owning one for 5+ yrs, tuning many of them including staged injection with dual fuels, custom injection/ignition schemes, etc...I wouldn't go *that* far. The GEMS board is nice, the AEM adapter is ok, the software and resulting firmware code leaves a lot to be desired. It's decent for the price.

The reason why I described the factory setup in detail is to make a point. In PnP config the ignitor controls dwell, but with any other ignitor you will need to customize the coil dwell table. This is very important - you can destroy your coils quickly.

These are the reasons I thanked you for clarifying and I am glad you mentioned the dwell control. I would hate to have people do this and start burning stuff up. I have left my dwell settings the same as what the dwell tables are set for an MKIV and have had no problems, but this is not to say there are not more efficient tables
 

IJ.

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Mar 30, 2005
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I come from a land down under
bfr1992t;1296918 said:
Uh-huh. I never said it wasn't.



After owning one for 5+ yrs, tuning many of them including staged injection with dual fuels, custom injection/ignition schemes, etc...I wouldn't go *that* far. The GEMS board is nice, the AEM adapter is ok, the software and resulting firmware code leaves a lot to be desired. It's decent for the price.

The reason why I described the factory setup in detail is to make a point. In PnP config the ignitor controls dwell, but with any other ignitor you will need to customize the coil dwell table. This is very important - you can destroy your coils quickly.
[thumb]http://ij.supramania.com/coildoh.jpg[/thumb]
 

Halsupramk3

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Apr 4, 2005
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X-man you stated

"You then have to turn off injectors number 4,5, and 6 and turn on/active injectors 7,8,9, and 10 and set them for primary under OPTIONS on the drop list. Then you go to FUEL, then ADVANCED FUEL, then INJ PHASING and set inject tooth #7 to 15.00, inject tooth #8 to 23.00, and inject tooth #9 to 7.00. Numbers 4,5,6, and 10 will have the number 0.00 in each of them."

what numbers go in inject tooth # 1, 2, and 3? originallly mine just has .5 in inj #1.

thanks.
 

X-man

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I used the injector phasing pattern for an MKIV TT. I edited the above post to include the settings I used.
 
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