The cheap ass's dual channel igniter

[Drifty Midship]

This is a write-up on how I modified 2 x 4AGE "041" igniters to function as a dual channel igniter.
It's for use in a DLI Wasted spark configuration with an aftermarket ECU on a 4AG.
I'm using Adaptronic ECU which controls dwell (charge time), so early toyota 'dumb' igniters were required.
The early 4A ones are actually good for this.
These igniters are falling edge meaning the spark is generated when the ignition signal from the ecu goes low after peaking to ramp up charge.
All aftermarket ecu's should have a config for setting ignition trigger as falling edge type.

I had access to 2 of these igniters and thought I would try this...

This explains basically how it needs to work, thanks to the nice people at Motec



Firstly take the igniters off the bracket that holds them to the coil.
Ditch the old coil as it's only single output and useless.

cracking the lid on the igniter will reveal the guts of it..



Snip the beige and red wires in the centre.
These come from the distributor.
The 4AGE that these 041 igniters come out of uses a VAST ignition system.
VAST operates a back-up ic running from the NE dizzy pick-up while cranking, switching over to the IGT signal for ignition triggering when the car is running.
So it's not required with Adaptronic cause it'll be using the IGT signal the whole time and the new ECU is smart enough to adequately manage the spark during cranking.



Here's the shielded cable to the dizzy removed.



Now chop some more wires. The feedback signal line IGF and NE back to ECU are not required... and the pale yellow one... cant remember what thats for...



At the igniter plug end chop the Blue IGT wire and the main 12V power wire.
Don't cut the wire right up against the plug. Leave a couple of cm of wire cause you might need to reuse the plug for something else later.
Always leave tails and service loops



Slide the heat shielding sheath off.
Now you should be left with only 3 wires connected to the igniter.

Something like this...



I left the tails on the wires in the igniter to allow me to rejoin in case i messed up
heatshrinked to insulate the unused wires and tidy it up (missed the green one by the looks of this pic!)



Some kind of silicone sealant for the now unused holes to keep water/moisture out.

[Drifty Midship]

Repeat the entire process above on a second identical igniter.

Once you have 2 igniters modified as above stick them on your mounting bracket of choice
join the brown 12V power wires on each igniter together.



These will ultimately connect to a 12v source.
In toyota systems it should usually be power supply south of the Engine Main Relay which activates when the ignition switch is in the ON position.

wherever you mount them make sure the mount can earth...
it is crucial that the igniter casings have a good connection to earth.
with this set-up I used aluminium for the bracket so I have had to use additional wires to earth the casings.
But if you are using a metal bracket and it is secured to the chassis then it will be fine.

The remaining blue wires go to the 2 individual ignition outputs of the ecu.
You just have to make sure that the output corresponds with the right igniter for the firing sequence.

And that's basically it...



Credit due to Autoshop101 website and the 2006 thread by The Witzl titled "Toyota Distributor and DLI Ignition Systems - explanation and guide" for helping me get my head around this stuff.

[MWP]

I came across some nice little dumb ignitors (really just a darlington transistor) in Mitsubishi Magna's... part number is Power unit J121.
They are bolted to the ign coil mount up near the passenger side strut top.

They are tiny, easy to mount, 3 wire (ground, coil & signal), and the pins are labled.
Im planning to use 4 of these with my Microtech soon.

Here is someone elses photo of it:


They are also small enough to put in your pocket at a u-pull-it style wrecker