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[JamesV6CDX]

The part i dont understand is we had the car running on all 6 with misfires on bank 1 on tickover.  That was with the 2 cams G & J in the wrong order...

So now we have swapped them round into there proper place and then the car dont wanna run on that bank at all, And only runs on 3.

Just to make sure we haven't been complete (insert male body parts here) - we need to check cams on the 2-4-6 bank are right too

[Steve B]

The part i dont understand is we had the car running on all 6 with misfires on bank 1 on tickover.  That was with the 2 cams G & J in the wrong order...

So now we have swapped them round into there proper place and then the car dont wanna run on that bank at all, And only runs on 3.

Just to make sure we haven't been complete (insert male body parts here) - we need to check cams on the 2-4-6 bank are right too

Never thought of that one 

[Marks DTM Calib]

Right well I am going to say it....diagnose it, don't go down the road of willy nilly part changes.

Every time you change something to 'try it' you add further risks and unknowns into the setup 

Start with the there basics, have you got

a) Spark on all 6 cylinders
b) Fuel to all six cylinders
c) Compression on all six cylinders.

If the answer to the above is yes then there is very little else that could cause a major issue.

[JamesV6CDX]

Right well I am going to say it....diagnose it, don't go down the road of willy nilly part changes.

Every time you change something to 'try it' you add further risks and unknowns into the setup 

Start with the there basics, have you got

a) Spark on all 6 cylinders
b) Fuel to all six cylinders
c) Compression on all six cylinders.

If the answer to the above is yes then there is very little else that could cause a major issue.

I take no offence at you saying it, because this is the approach I've always tried to adopt (having learnt it from yourself ), and is why I was reluctant to change the engine loom, when it was fine before it's original Cambelt change

The answers to the above questions, are:

a) Yes
b) Yes
c) Yes

[Kevin Wood]

Bear in mind that if it has been fuelling very rich, it may have fouled the plugs. This is especially true any time you keep starting an Omega to try things. The cold start enrichment eventually starts fouling plugs and you end up chasing a misfire that isn't your primary problem.

We ended up in this trap when the silver bullet developed a couple of noisy tappets following its' LPG conversion. The misfire in addition to the tapping noise convinced us that we'd done something more serious, thus we didn't want to run it for long, but the fact is that once you've started it a few times, you will have fouled the plugs. Vicious circle.

[Marks DTM Calib]

I take no offence at you saying it, because this is the approach I've always tried to adopt (having learnt it from yourself ), and is why I was reluctant to change the engine loom, when it was fine before it's original Cambelt change

The answers to the above questions, are:

a) Yes
b) Yes
c) Yes

So, in the case of ignition, are you getting a good enough spark to light the fuel e.g. it will clear a 35mm plus gap at atmospheric pressures?

[Steve B]

I take no offence at you saying it, because this is the approach I've always tried to adopt (having learnt it from yourself ), and is why I was reluctant to change the engine loom, when it was fine before it's original Cambelt change

The answers to the above questions, are:

a) Yes
b) Yes
c) Yes

So, in the case of ignition, are you getting a good enough spark to light the fuel e.g. it will clear a 35mm plus gap at atmospheric pressures?

We had coil pack out fitted plugs into it and earthed the plugs thread and then cranked the engine over..

I think james may agree in saying the spark we saw,I dont think it could clear 35 mm 

[Marks DTM Calib]

Ok, so a big issue there then, at atmospheric pressures it should clear a good 35mm.....if they look weak using your test then you have NO hope under compression.

A few quick easy tests to do are

1) With the engine running measure the voltage between the 0V connection on the coil pack and the battery neg

2) With the engine running measure the voltage between the 12V connection on the coil pack and the battery pos

[Steve B]

Ok, so a big issue there then, at atmospheric pressures it should clear a good 35mm.....if they look weak using your test then you have NO hope under compression.

A few quick easy tests to do are

1) With the engine running measure the voltage between the 0V connection on the coil pack and the battery neg

2) With the engine running measure the voltage between the 12V connection on the coil pack and the battery pos

James did do this before we swapped the cams G&J back and had good reading. However Since then is when this new problem came so i am unable to do this on my own owing to cannot no longer get engine to tickover

So i can only do it at the moment with ignition on.

1) 11.97v

2) 11.87v

Across batt 12.2v

[Steve B]

Scrap readings above. Got a gas pedal helper

Engine running @ 2000rpm

1) 14.4V

2) 14.3V

[JamesV6CDX]

I have to be honest I thought the spark looked a little weak on both banks.. And at one point I thought 1 3 5 was only sparking intermittently... But couldn't replicate that

[Steve B]

Scrap readings above. Got a gas pedal helper

Engine running @ 2000rpm

1) 14.4V

2) 14.3V

With these readings it makes it look like a coil pack issue or plugs ..Well today plugs have been changed.And i have two other known good coil packs here to try (one of them is yours james) And its the same result.

When plugs are removed they are soaked in fuel. And with a torch down bores i can see soaked in fuel
When 1,3,5 coil pack is unplugged the car runs better. No popping etc No more being held back.

[Marks DTM Calib]

Interesting....so with the 1-3-5 coil pack disconnected then there is no popping etc?

The voltage readings prove there is no volt drop in the supply and return cabling.

[Steve B]

Interesting....so with the 1-3-5 coil pack disconnected then there is no popping etc?

The voltage readings prove there is no volt drop in the supply and return cabling.

That is correct and it will sort of then tickover on one bank..

[Marks DTM Calib]

Which hints towards the coil pack being fired on the wrong stroke for some reason.

So other than the cylinder head, nothing else has been changed?