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[Kevin Wood]

Have you tried running it with the MAF disconnected?

It will complain, obviously, but it will substitute reasonable values for the fuelling that should make it run without a misfire.

Can you read live data? If so, check the MAF reading at idle and fast idle (e.g. 2500 RPM). In addition, see what the fuel trims are doing.

Kevin

[Marks DTM Calib]

To me, its not coil packs or lambdas for the simple reason as I dont buy into multiple simultaneous failures (there being 6 coils and 2 lambdas).

The MAF can and will affect the running in such a way.

The coolant temp can do some starnge things but, it would run fine when cold or when hot an not both under such a fault.

Hence the MAF adn the need to look at live valves as the data from this determines the basic fuel mix for ALL cylinders which is then tweaked by the fuel trim from the lambdas.

[markspark]

this is just a stab in the dark as i don't really know how it works but could this not be a fault on the traction control as that gives the impression of a miss fire to me, i understand the car has to be driving for this to work but faults can appear in may forms if this is total gaga and wrong sorry (its just a thought)

[joshwyatt]

Unplugged the MAF, and no noticeable difference.
I know that James and Jamie have extensively looked at live data figures etc, and they may have looked at fuel trim values, and MAF values etc, I know James looked at coolant temp sensor etc so I think a fair few things have been discounted.
I'm just trying to find my camera, as that also takes video clips...I think that may be the best thing to do, so people can see exacelty what I'm talking about.

[JamesV6CDX]

Unplugged the MAF, and no noticeable difference.
I know that James and Jamie have extensively looked at live data figures etc, and they may have looked at fuel trim values, and MAF values etc, I know James looked at coolant temp sensor etc so I think a fair few things have been discounted.
I'm just trying to find my camera, as that also takes video clips...I think that may be the best thing to do, so people can see exacelty what I'm talking about.

I still think it's wiring to the coil packs  :-/

[joshwyatt]

Unplugged the MAF, and no noticeable difference.
I know that James and Jamie have extensively looked at live data figures etc, and they may have looked at fuel trim values, and MAF values etc, I know James looked at coolant temp sensor etc so I think a fair few things have been discounted.
I'm just trying to find my camera, as that also takes video clips...I think that may be the best thing to do, so people can see exacelty what I'm talking about.

I still think it's wiring to the coil packs  :-/

Could well be James...but now it's missfiring on the 2-4-6 bank aswell so it's not just the 1-3-5 side. Your idea of the loom itself seems like the most plausable idea, I wonder if heat has broken down the connection somewhere and is now effecting the 2-4-6 side.
If the heads were off it, and recon head fitted in it's previous owners time, is it possible a wire could be trapped or something not fitted correctly?

[Kevin Wood]

Unplugged the MAF, and no noticeable difference.
I know that James and Jamie have extensively looked at live data figures etc, and they may have looked at fuel trim values, and MAF values etc, I know James looked at coolant temp sensor etc so I think a fair few things have been discounted.
I'm just trying to find my camera, as that also takes video clips...I think that may be the best thing to do, so people can see exacelty what I'm talking about.

I still think it's wiring to the coil packs  :-/

From memory, the coil packs have a trigger signal to each coil driver from the ECU in addition to a +12v supply and Ground signal.

It's very unlikely that all trigger signals have gone AWOL together so that leaves the +12v and ground. I guess it's possible (likely) that both coil packs share the same supply and ground connections so they might be worth a look.

In addition, don't know if the ECU shares the same ground or a different one, but, if grounded to a different point, that might be worth a look too. I know for a fact that the coil pack supply comes directly from the ignition switched feed whereas most other engine management parts are fed from the main relay under the bonnet.

Also, the misfire could be fuel related, so injector wiring worth a check, as is fuel pressure / flow to the injectors.

Kevin

[Marks DTM Calib]

No, the coils dont work off triggers they are coils with a Pos supply and low side drive.

And my experience of the MAF faults is that unplugging makes little difference (as per Mr Dundee's)

I dont buy coil pack wiring either as thats a multiple failure.

I would check the main engine 0V connection (but dont hold out much hope)

[Marks DTM Calib]

Injector wiring fault would throw a code.......

[Marks DTM Calib]

.........and is again multiple failures

[joshwyatt]

There's a short video here, the camera used isn't great, but it's all I had available, there's also an iregularity with the sound, but this is due to the camera and not the vehicle. (Best viewed with the sound turned up fairly high) A cup of blue water is on the plenum so you can see how it vibrates. It is started from stone dead cold, the camera isn't of sufficient quality to really capture what it's like. It cycles through initial start up showing plenum then to exhaust, then back to plenum after been running for two minutes then back to exhaust. The dash shot shows the idle as being fairly steady, but this gets worse after a short period.
It's not a good quality film, I'll endevaur to try and produce a better one.
The symptoms steadily get worse, the idle begins to hunt and nearly stalls but it keeps itself running.
I appreciate there will always be vibration on the plenum, but I've had three 3.2's and none were anything like this.
If I'd continued to film you see it gets worse and the whole engine appears to shake.

[mrjimbo]

I had a similar type of thing happen on Judd V8 a couple years ago, we looked high and low, injectors, leads, plugs, coils, cps, throttle pot, striped the engine loom looking for chaffing, all the sensors etc checked all the wiring in the cockpit as well and couldn't find anything. After messing for 3 or 4 days the owner decided to have the engine out and send it back to Connaught for a strip and inspection so we started disconnecting everything and then we found the problem, the main plug to the engine ECU had become damp inside the rubber seal(it shouldn't have done as it was located inside a sealed box inside the cockpit) we dried it out and cleaned it thoroughly and put everything back together and the missfire had gone completely. This may not be the problem with yours but it's always worth having a look just to make sure just to rule it out   

[Marks DTM Calib]

Sounds very much like a MAF reading high Josh.

At cold when on enrichment then its better, as it warms up and goes off enrichment it gets worse.

As said, I have seen a few that read high and live data would confirm this

[joshwyatt]

Sounds very much like a MAF reading high Josh.

At cold when on enrichment then its better, as it warms up and goes off enrichment it gets worse.

As said, I have seen a few that read high and live data would confirm this

Thank you Mark, I certainly appreciate your imput in this...I know when everyone's out of ideas...they all ring you up to ask you what you think 
I'll get a live data read on the MAF. I think a code reader is going to be the next thing I'll need to invest in.

[Marks DTM Calib]

For info, its a pretty common bosch item part number 0280 217 121 or 5WK9600 and is use on Citroens (2.8 HDi Relays), Vx 2.6 and 3.2 V's, Vx Vectra and Frontera 2.2Dti's and 2.8 Jtd Fiats