Which ignition coil is bad?

[goldNSX]

My engine has a bad ignition coil on the rear bank due to bad gaskets. Only recognizable at idle. Resistance is 1.1 Ohm equally distributed. How to find out which one is bad (before exchanging all three of them)?

 

[drew]

I suspect you have a torn boot that is arcing the spark. Look for that.

but you can swap them one by one with the other bank to see when things change.

Drew

 

[D'Ecosse]

Probably easier to just pull each off individually at a time & see which affects the idle least - or alternatively do same but pulling off each injector connector.

 

[Daedalus]

You could also disconnect the coils (or injectors) one at a time to see which one doesn't make a difference. If it has been doing it long enough you can usually tell by pulling the plugs. Look for surface damage and/or dark carbon traces.

 

[D'Ecosse]

Echo! Echo! Echo! Echo! Echo!

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Ha! Beat you by 5.739 ms Daedalus

 

[Daedalus]

My post took 8ms longer to type.

 

[goldNSX]

LOL!
Maybe I can pick up an used ignition coil at my garage and try it in each place on the rear bank.