oh good your here, I was worried something had happened.

 

You're the one who's in the fantasy world.
It got explained towards the end of this one with a proper diagram.

https://www.evolutionm.net/forums/ev...-setup-11.html


You even commented yourself so you can't say you didn't read it.
More likely it's beyond your understanding abilities and as such you really shouldn't be posting in tech sections, just stick to asking questions.


As for the 30KV, well it's not 30KV (the KV across the plug varies with cylinder pressure), to pass current through a 12v battery the wrong way, it takes just a bit more than 12v. No different from a battery charger.

 

Sorry. Trying to keep it upbeat.
I hope he knows that a 12V battery charger is hooked up in parallel to battery and what he's claiming with spark going through battery is in series. Hard to confuse the two but he knows everything.

Anyway, I hope OP finds a way to keep his COP working longer. Many have used it long term, so it is possible. Keep making one change at a time until you find the source of your problem. Good luck and don't get discouraged by nay sayers.

 

1. Gap your plugs at .020"

2. Is is the same cylinder always seeing the failed coil? If so, wiring is likely the culprit. If not, where are you purchasing the coils from and are they real Denso coils or cheapies?

 

Can you see signs of what failed on those Denso COPs?

 

Unfortunately, when I labeled the coils after the first failure, I do not remember if I put them back in the same positions, so I can't decisively determine if the failure occurred in the same position. However, it wasn't the same coil label that failed, and I'm a creature of habit, so it likely wasn't the same position which failed this time. I'll be sure to keep the coils in order this time to verify which one dies next. To answer you follow on question, these are genuine Toyota branded Denso coils P/N 90919-02240.

No, they aren't even overheating when they fail. I have routinely pulled them out by hand on the side of the road while diagnosing which one has gone bad.

 

So they are failing internally? No burn marks from spark getting out?

 

BPR7ES (OEM plugs for the 8, except they're copper) work until you're over about 750whp. Gap to .020" and send it.

 

Oh thats good to know, for some reason i thought BPR where half a step colder then stock.

 

No, the "P" means they're extended tip. So the BR7 you suggested is actually half step colder because the tip is right at the end of the threads.

 

oh man i really had that backwards. I thought the protruded electrode is what made it that half a step colder.

 

Thanks for the suggestions guys, I've got new plugs and a new coil to continue on with. I'll gap them to .020 and take better notes about which coils are where. Fingers crossed. If I can make it through both season opening autoXs without a failure, I'll be content. They're 300 miles away, so I might run the OE coils for the commutes.

 

...ANNNNNND another coil died. That's three total so far.

I've tried using copper plugs, changing the gaps, etc.

Time to add those additional ground wires.

At this point though, I'm tired of replacing coils.

Is anyone else having this same rate of failure on the coils? Doing a search I find plenty of people having misfires, but not from failed coils per se.

 

Additional grounds aren't going to do anything. I think you're leaving the plugs in for too long, and the rich AFR certainly doesn't help. I change copper plugs in my car every 5k miles or so, gapped to .020". If I let them go 10k miles I would start getting misfires on the stock coils.

 

if you still have all the failed ones, you could remove the potting material and see if they have a common failure mode. It would also give you the ability to easily verify if they are knockoff's or something like that.