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Discussion Starter #21
New update, so I narrowed down my searching and found that my middle coil pack wasnt producing any spark, which was weird since its brand new, come to find out that the bottom of it blew out, this is the second time it's happened to the middle coil pack, anyone have any idea what would cause a pack to crack and potentially "blow up"? I know a lot of people point towards the ECU when there's issues with ignition or spark but I checked it recently and everything looks in order. I'm stumped and I really want this car running as it's my only vehicle at the moment.
 

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93 NA ATX 3000gt DOHC
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My first question would be, where are you buying these coils from? It’s not likely the ECU or PTU could cause a coil to split.
 

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Discussion Starter #23
I
My first question would be, where are you buying these coils from? It’s not likely the ECU or PTU could cause a coil to split.
I ordered the first one that blew up from 1AAuto, I figured I'd try their parts for once, that was a mistake, the others I got from autozone, nothing real fancy.
 

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Hard to imagine two bad coils from to different venders. You might want to make sure you have power wire (Black with white stripe) to positive side of that coil, should be same side as the other two. Not sure if that would cause coil to split but can't think of anything else right now.
 

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Discussion Starter #25
I
Hard to imagine two bad coils from to different venders. You might want to make sure you have power wire (Black with white stripe) to positive side of that coil, should be same side as the other two. Not sure if that would cause coil to split but can't think of anything else right now.
I talked to some of the guys I work with in my shop and they said it's most likely getting too much power to the coil, I wanna say the last PTU was what caused the coil to blow up because it was a cheapo Amazon one, but I do have a spark plug wire that needed to be repaired, I wrapped it tight with electrical tape to insulate. It very may well be either the PTU or the spark plug wire causing it, unless its shorting somewhere but I highly doubt it.
 

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I talked to some of the guys I work with in my shop and they said it's most likely getting too much power to the coil,....
All coils are feed battery voltage from the 15amp #12 fuse in fuse panel under dash. It would be almost impossible for higher voltage (from alternator maybe) to get to coil without increasing amps high enough to blow that fuse. That’s one of reasons I wondered if there was a chance the battery voltage might be hooked to negative terminal of that particular coil, instead of positive terminal where it should be.

The PTU only makes and breaks the ground for negative terminal of the coil, it does not supply power in any way. If it fails it simply would not allow coil to operate, not add any more power. Spark plug wire arking to ground would just cause misfire, the coil doesn’t care whether power goes thru plug or not it’s still doing its job.
 

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Discussion Starter #27
All coils are feed battery voltage from the 15amp #12 fuse in fuse panel under dash. It would be almost impossible for higher voltage (from alternator maybe) to get to coil without increasing amps high enough to blow that fuse. That’s one of reasons I wondered if there was a chance the battery voltage might be hooked to negative terminal of that particular coil, instead of positive terminal where it should be.

The PTU only makes and breaks the ground for negative terminal of the coil, it does not supply power in any way. If it fails it simply would not allow coil to operate, not add any more power. Spark plug wire arking to ground would just cause misfire, the coil doesn’t care whether power goes thru plug or not it’s still doing its job.
So what you're saying is when I replaced the coil I may have accidentally switched the wires around? I was thinking it may be a possibility that I might have made that mistake but I'm not sure. Once I go to install the new pack tonight I'll look at the others and see if I had it wrong.
 

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Just to clear up what might cause some confusion. The Black wire with white stripe I talked about being power supply wire, would be in harness side to coil pack connector. The coil pack (device) side of connector, might be a different color (like red maybe). It will be the one that jumps from coil to coil all on the positive post for each coil.

The negative wires from each coil will be individual wires to the connector, they’re usually Blue wire with different colored stripe for each coil.
 

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Discussion Starter #30
Just to clear up what might cause some confusion. The Black wire with white stripe I talked about being power supply wire, would be in harness side to coil pack connector. The coil pack (device) side of connector, might be a different color (like red maybe). It will be the one that jumps from coil to coil all on the positive post for each coil.

The negative wires from each coil will be individual wires to the connector, they’re usually Blue wire with different colored stripe for each coil.
Well I made sure everything was wired and connected properly, put the new coil in and tried to start it, I had a buddy of mine check for spark and now I'm not getting spark to any coils, even the new one. I dont know what the issue is from here and it feels like I'm running in circles.
 

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First check for power to the coils with switch turned to “on” position. If no power there check the #12 fuse inside that I mentioned, it would be middle row far right fuse.
 

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Had same issue on my old 91 car died had replaced about everything including ecu. Ended up replacing the engine harness and started right up ran fine after never had an issue there after had a bad wire some where and wasn't getting spark never could find what wire It was took the whole harness apart. Just a thought but have a 94 now have a similar issue but when car is cold it will feel like it's missing when under a load was the coolant temp sensor to the ecu was causing it to run rich. And spark plug gap can cause if to run like crap when cold too. But I'd check and see if you are getting signal to the coil packs to fire can check before ptu and after at coils just need a multi meter same with cam and crank sensors but check impedance on them and see if they are reading when motor is being cranked. One thing I've learn with owning these cars is to suspect the uninspected. They drive you not with little issues that are hard to find. Best thing is to set down and check each sensor can get values online for them. And check the wires going to everything one bad ground can cause a ton of issues. And invest in a aftermarket ecu best thing I've done for sure. Laptop is always handie to figure out what isn't reading right. Pricey but can save you tons in parts and headaches but then you also have to learn how everything works. But hope you've figured it out know it's been a few weeks since this last post but hope it helps.
 
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