VN Calais 3.8 Backfiring After Coil Pack Changeover

[VNCalais3800]

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]

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

[Greedy]

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]

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]

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

[VNCalais3800]

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]

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/...ine-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

[88GreenVN]

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

[VNCalais3800]

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]

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...

[rob drag racer]

here ya go this is correct http://forums.justcommodores.com.au/...ine-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

6-3 2-5 4-1
Front of Vehicle
already done

[88GreenVN]

I just looked and it goes

6/3 5/2 1/4 looking from the front of the car right to left.

This is the order to plug your leads onto the coils

[VNCalais3800]

Thanks guys much appreciated.
Ill go have a look and see if i can find what is wrong

[rob drag racer]

heres a picture i flogged from ebay

[VNCalais3800]

rob drag racer thanks for the pic, i realized when i was installing the coils that the DFI module under neath the coils has the numbers printed on it, of which cylinder spark plug lead goes to what coil.

I ended up swapping the DFI module back to my original one and it runs a lot better with no backfire.
Unfortunately now it has a slight hesitation when i accelerate, any ideas.

[rob drag racer]

rob drag racer thanks for the pic, i realized when i was installing the coils that the DFI module under neath the coils has the numbers printed on it, of which cylinder spark plug lead goes to what coil.

I ended up swapping the DFI module back to my original one and it runs a lot better with no backfire.
Unfortunately now it has a slight hesitation when i accelerate, any ideas.

try the IAC valve maybe dirty it could also be bugged and ya welcome for the pic i thought you had just gone without taking another look at the forum lol

[VNCalais3800]

Thanks rob drag racer.
Whats the best way to go about cleaning the idle air control valve.
Gone!! me, no way, i need my daily JC fix. lol

[rob drag racer]

remove it from the tb hit it with some carby cleaner in a spray can making sure you remove all the carbon from the gutters on the shaft (you will see what i meen when its out) let it dry and put it back in job done

[VNCalais3800]

Ill give it a go and see if it improves it.
rob drag racer hows your race status going.

[rob drag racer]

at the moment it aint im in the process of putting a ford on the road as my vp is starting to knock (bearings are rooted) and i cant be bothered fixing it and i need a tow car so yeh my attention is sorta elsewhere atm but once thats on the road hopefully ill be back to the vn still got a diff change to do yet