Morning Pete, thanks for your reply.

Over the last week I've had it on the gas analyser and conducted a BET Test which it passed with flying colours.

I've also had a Launch CRecorder installed for 24 hours which showed up nothing of interest.....not even a DTC.

It was serviced not that long ago by myself and has 5W/30 fully synthetic oil in the engine and I only use NGK plugs which are the correct part number.

I'm going back to it for a couple of hours today to run some more tests including cylinder compressions and a manifold vacuum check which I didn't have time to do last week. I've got a dual-channel scope and will scope the primary coil signals from the PCM and post the traces on here for reference.

I forgot to mention in my first post; the misfire is only present under load and isn't evident with the vehicle stationary at idle or when the engine speed is increased.

Jon