Overloaded the ignition coil- Ignitor damage too?

[vinu_neuro]

I ran a compression test recently and forgot to pull the power to the distributor. Consequently I damaged the ignition coil since the charge probably built up and internally shorted it without any ground to dissipate to. Coil damage showed up on the multimeter for secondary winding resistance far lower than spec (8Kohm vs. 13-20).

So my question is would the ignitor have been damaged too since it would've been the only path for the current to flow? The primary winding resistance is within spec. Ignitor is running the distributor fine right now, but I don't want to be stranded because of it in the future, nor do I want to spend $60+ for a new one if unneeded. This seems like a straightforward problem, I'd be grateful for anyone with an electrical background to give some guidance. Thanks.

 

[229]

It is possible to damage electrical circuits all the way back to the coil drivers in the ECU computer, if we are talking about modern vehicles, from even having misfiring sparkplugs. I say replace the ignition coils and see if it runs or not. If you wanted to test for weakness it would require an oscilloscope and a properly trained mechanic to know how to interpret the data.

 

[vinu_neuro]

Swapped a spare coil in from a friend and that did the trick. What I want to know is if the ignitor would have been stressed because of this. Electricity is straightforward in the way it operates, any EE's here?

 

[Tegger]

Originally Posted By: vinu_neuro
Swapped a spare coil in from a friend and that did the trick. What I want to know is if the ignitor would have been stressed because of this. Electricity is straightforward in the way it operates, any EE's here?

Not an EE, but I can say it's very unlikely the igniter will have been damaged to the point where you'd notice. No worries.

Next time, if you want to preserve the coil during such an operation, pull the ignition fuse (probably #1 on your car), or unplug the electrical connectors at the distributor before cranking.

 

[mechtech2]

Coil are most likely.
The igniter was probably not affected by this.