WJ 4.7HO - Ignition Coil Error(s) after engine work

[art^69]

Hi everyone.

I could really use some help on this one. I'm stumped.

I've just replaced the valve stem seals on my 4.7 to cure the common idle smoke issue. This was done with the heads still on the car using the compressed air method. This engine purred (smokily) prior to the work.

Obviously I've had to disconnect and remove a few things to access the seals. Injectors, Ignition coils etc, and any wiring that was in the way.

Apart from the mechanical work I also used this chance to have the injectors overhauled and tested by Bebco in Sydney. This is a place I trust and know they would do a good job.

I've also replaced all 4 oxygen sensors using Denso's, because the only fault that I ever had (prior to this engine work) was O2 codes being thrown up which was confirmed by my excessive fuel consumption and black plugs.

And I fitted NGK Iridium plugs too.

Now that I've put everything back together it idles like an absolute pig and has misfires on one, or several, or all cylinders. Ive had the full range of error codes from P0351 to P0358.

To diagnose the problem I've done the following.
1. Checked all wiring and connectors.
2. Swapped out the ASD relay with a known good relay.
3. Checked the battery voltage and alternator voltage. All good.
4. Reduced the gap on the NGKs to .035. Just in case.
5. Swapped out the plugs to OEM Champion Platinums.
6. Swapped out all 8 Ignition Coils with known good coils.
7. Rechecked all wiring and connectors which were unplugged. Checked all the pins.
8. Swapped out the idle control solenoid too.
9. Reset the PCM several times, after changing some of the above.

Nothing has worked. Occasionally it runs fine for a few minutes but then idle drops and it runs rough or stalls. The exhaust is spitting out black, and unburned fuel..

So now I ask for some help from the wealth of knowledge on AJOR. Has anyone ever had not one but multiple ignition code errors.

Thanks