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Melted VZ Coil Pack

Colin_R

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Hi,
I am new here and wondering if anyone can offer some thoughts or advice. I have a 2006 VZ, 120,00-km log book serviced from new. I recently had a new ECU fitted. Cost a fortune. two days ago I started the car from cold and the check powertrain warning light came on. Engine was misfiring. within a few minutes of idling, smoke was coming form under the bonnet. Mechanic says a coil pack was melted and he says he has not seen one like that before. a complete new set of coils packs were fitted and mechanic says engine still misfiring and one complete bank ( injectors cylinders?) is not working according to the fault codes. He needs to investigate further but suspects the ECU is blown .
Having just coughed up for an ECU i an hoping it is not that. My question is, could a faulty ECU fry the coil pack? I would be appreciative of any thoughts anyone may have on this

Many Thanks
 

aussieakito

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strange to happen like that but i suppose it could happen, usually when its missing on one whole bank its something like an earth, which i suppose would also make sense because it would cause more resistance in the coil (heating up more) causing it to melt?
otherwise it could be timing chains which are fairly common but if they havent been noisy and its been serviced regularly i cant realllllly see it being too much of an issue.
 

Colin_R

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Thanks Aussieakito, sure is strange. No noise from timing chains. It has been pretty well looked after.
 

diysv6

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VF S1 SV6 STORM A6: VZ S1 SV6 A5
IMG_1532ml.jpgVZ Schematic part 2.jpgVZ Wiring schematic.jpg

I have attached a member's schematics contribution (many thanks again) which show the ECU and the interconnects with various supply fuses. I found this very helpful when I had to replace my ECU last year.

Looking at my notes about the ignition coil it has a raw 12v feed via the "ignition on" function. A common 12 v feed to each bank's coils and fuel injectors is via an individual fuse under the bonnet.

The ECU supplies the trigger pulse to the get the high voltage ignition coil circuit to trigger etc. I don't think the ECU can supply a destructive current to cause melting as you have described. Perhaps arcing occurred, damaged a component which then allowed the raw 12v to further melt components etc.

To cause melting, not a high voltage burn through arcing etc, I think your coil has failed in the 12v supply area, not the ECU trigger area.
As other members have suggested, check the common earth point for the ignition coils 1,3,5 and 2,4,6 on each bank. They are located below the wiring loom carrier along the top of each cylinder head. Also check underneath the relay block under the bonnet for damaged wiring into the related fuse holders, relay sockets etc, for burnt, melted or charred hard wiring insulation. You might have a 12v supply problem causing the ongoing miss in the cylinder bank - this can impact on coils and injectors .
EDIT. I have attached a sketch of the 12v feeds around the ECU from my SV6 5sp sedan.

Hope this helps.
 
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scott.dellow1

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Hi,
I am new here and wondering if anyone can offer some thoughts or advice. I have a 2006 VZ, 120,00-km log book serviced from new. I recently had a new ECU fitted. Cost a fortune. two days ago I started the car from cold and the check powertrain warning light came on. Engine was misfiring. within a few minutes of idling, smoke was coming form under the bonnet. Mechanic says a coil pack was melted and he says he has not seen one like that before. a complete new set of coils packs were fitted and mechanic says engine still misfiring and one complete bank ( injectors cylinders?) is not working according to the fault codes. He needs to investigate further but suspects the ECU is blown .
Having just coughed up for an ECU i an hoping it is not that. My question is, could a faulty ECU fry the coil pack? I would be appreciative of any thoughts anyone may have on this

Many Thanks
Hey Colin, how did you get on with this problem, I am just reading it. Exactly the same thing happened to me yesterday to my 2006 Holden Adventra, Started it cold in morn and 1 coil started smoking straight away , Would love to hear how you resolved this problem
 
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