Honda F4i IGN coil failures

[tommy]

We've blown one of the stock denso coils. It split itself into two at about 2.5 in from the top.

We are running a MOTEC M4 with 3ms of ign dwell time, fired by Bosch ignitors.

Since this is our first failure after a good amount of running, I want to say this was a bad coil, but out of curiosity what have you all seen as causes of blown coils? thanks...

[tommy]

We've blown one of the stock denso coils. It split itself into two at about 2.5 in from the top.

We are running a MOTEC M4 with 3ms of ign dwell time, fired by Bosch ignitors.

Since this is our first failure after a good amount of running, I want to say this was a bad coil, but out of curiosity what have you all seen as causes of blown coils? thanks...

[bigtoyota9]

We had the same type failure on the dyno, they just overheated and melted in half, it happened to only two of our coils. It turned out to be the new igniter pack that we were running and the way we had it wired. What would happen was when we had the power to the Motec and igniter on, and the engine not running it would ground the other side of those two coils and basically run current through them non-stop. This just overheated them and melted them to mush, terrible smell too. We switched the Motec to sequential spark and changed the wiring of our igniter pack and haven't had a problem since. We still consciously check to make sure that the car doesn't stay turned on without running for extended periods of time. Hope your car is running well, see you in Detroit.

[AZWildcat]

You can add us to the coil list... just happened to us tonight, #4, same circumstances as described above though we're running an AEM.

Dennis Walsh
http://www.wheelkinetics.com/hre/supra/suprax.jpg

[Dan Deussen @ Weber Motor]

The permanent positive (+) side of the coils and injectors should be switched on only when then engine is cranking. This can be achieved by using the fuel pump relay output that most ECU's have to also switch a relay for injectors and coils.

I would think that should solve at least part of the problem you guys are experiencing.
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