Wasted spark ignitions

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Flopearedmule

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Could someone help me understand how these coils fire? I know they get a signal from the ECU, but what is the signal? 5v?
How can I do a bench test and make them fire the plugs?
I know they are wasted spark, and one pin fires 1 and 4 the other pin fires 2 and 3.
Thank You
 

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Do you have more information about it?
Is that the igniter for the gas stove?
 
Regarding the ones in the pictures without the aluminum case, 12V is normally connected to the center pin which is shared with both of the internal coils. To fire one side, the corresponding pin is momentarily pulled to ground with points or a drive transistor and the coil fires between the two corresponding coil outputs through the spark plugs. The coil with 4 pins, two of the pins probably get tied to the 12 volts instead of the one. You could put short pieces of wire on the outputs pointing at each other and it will jump a spark there. When you use spark plugs, the threaded part of the plugs will need to be connected together.

The one in the pic with the aluminum cover, it probably has the drive circuitry built into it, not sure about drive voltages, but probably uses similar 12v and pulling a pin low or high to drive it. I have not played with ones like that one.
 
Last edited:
Regarding the ones in the pictures without the aluminum case, 12V is normally connected to the center pin which is shared with both of the internal coils. To fire one side, the corresponding pin is momentarily pulled to ground with points or a drive transistor and the coil fires between the two corresponding coil outputs through the spark plugs. The coil with 4 pins, two of the pins probably get tied to the 12 volts instead of the one. You could put short pieces of wire on the outputs pointing at each other and it will jump a spark there. When you use spark plugs, the threaded part of the plugs will need to be connected together.

The one in the pic with the aluminum cover, it probably has the drive circuitry built into it, not sure about drive voltages, but probably uses similar 12v and pulling a pin low or high to drive it. I have not played with ones like that one.
Thanks Scott
The one that might have the circuitry built into it, I’m interested. It looks like this one is used in VW cars. I’ll try to get to a dealer this week and maybe they will give me a schematic. I’m hoping it might be just a 5 volt signal, I can then use a Hall effect to make it spark.
 
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