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VN Calais 3.8 Backfiring After Coil Pack Changeover

VNCalais3800

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Hi all,
Recently my VN Calais S1 has started to run like it was only firing on 3 or so cylinders (dont worry it has not left the shed). I replaced the coils with champion coils they cost me $58 each at repco. I also changed the spark plugs to the iridium/fusion ones cost me $140 at Supercheap and changed the leads to blue bosch high performance ones they cost me $80 also from supercheap. After $300 odd bucks it now backfires.
Checked and rechecked the OBD with the ALDL bridged, displays code 12 Operation is as normal. Checked and rechecked the spark plug lead order. Replaced the Module under the coils.

I should ad when i was driving the VN a couple weeks before this happened the idler pully (pathetic plastic one) bearings wore out and melted the pully as a result the belt slipped in towards the engine, due to being in traffic had no choice but to keep driving it to a open park. Would this affect the timing as the belt was slipping on some pulleys and not on others? and if so how do i go about rectifying the problem.

Any help would be much appreciated and Thanks In advance.
 

Leebo

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I once got a faulty set of leeds from repco, check them with a multimeter are they on the right firing order?
 

Greedy

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Gotta be carefull with leads if the dont have the insulator for the top of the plugs they dont seem to run right i dont understand why. I had a set of qld 10 mm ignition leads with no insulators and it miss fired sometimes. Holden said to put insulated ones on i should be fine after that everything was fine. I dont know if this is your problem or not.
 

rob drag racer

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I should ad when i was driving the VN a couple weeks before this happened the idler pully (pathetic plastic one) bearings wore out and melted the pully as a result the belt slipped in towards the engine, due to being in traffic had no choice but to keep driving it to a open park. Would this affect the timing as the belt was slipping on some pulleys and not on others? and if so how do i go about rectifying the problem.

Any help would be much appreciated and Thanks In advance.
this makes no difference to the timing its set by the ecu the coil pack/dfi/cas/ecu replace the old dizzy ya can run without a belt with no problems it will get hot and the battery will die but you get my drift
 

88GreenVN

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I'd guess the leads may be on wrong. I did it to my V6 one day. Not good - but easy to do.
 

VNCalais3800

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Hi,
I have been relying on the haynes manual the diagram shows the order is.
6[]5
4[]3
2[]1
(Radiator) Front Of Vehicle

and shows the coil pack as
6-3 2-5 4-1
Front of Vehicle

Is this correct as i cant find anything about the firing order in the Gregory's
and from what i have read online it seems to be different.
My ride is a VN Calais V6 1989 Series 1 with the Series 2 coil setup.
 

rob drag racer

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Hi,
I have been relying on the haynes manual the diagram shows the order is.
6[]5
4[]3
2[]1
(Radiator) Front Of Vehicle

and shows the coil pack as
6-3 2-5 4-1
Front of Vehicle

Is this correct as i cant find anything about the firing order in the Gregory's
and from what i have read online it seems to be different.
My ride is a VN Calais V6 1989 Series 1 with the Series 2 coil setup.
here ya go this is correct http://forums.justcommodores.com.au...l-specifications/2640-vn-v6-engine-specs.html

so yes your right Firing order 1-6-5-4-3-2 from the front of the engine left bank 2-4-6
right bank 1-3-5 i also checked the coil pack configuration against mine that's right to
 
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88GreenVN

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the cyclinder order is correct. As of the coils not sure of the SII
 

VNCalais3800

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I understand where the cylinder numbers are but i dont get which spark plug lead goes to which of the 3x round coils as they are the aftermarket one's for series 2 they dont label them with numbers.
 

88GreenVN

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I understand where the cylinder numbers are but i dont get which spark plug lead goes to which of the 3x round coils as they are the aftermarket one's for series 2 they dont label them with numbers.
I'll go look at the car sitting out the front - hang on...
 
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