Missfire - the car performed perfect during the test drive, but I was assured it would missfire at some stage. Driving to work the next day, sure enough after about 30mins driving, it dropped a cylinder. Luckily I was only a few minutes from work, where I have a nice garage area for me to play with cars in my lunch hour!
Upon inspection, there was piles of rat crap and rat piss stains around the coils. So a quick plug change turned into a few hours of cleaning and inspecting all the various parts where a rat had called home.
After cleaning it all out, and pulling the coils out, cleaning out some more, I had the plugs out. They looked OK, a set of NGK Platinums. In went a set of trusty old BCPR6ES's, as I've had good results with these in the past.
While putting the puzzle back together, I noticed that Coil #1 had been chewed up by the rat around the boot quite a bit. The car came with a spare set of Splitfires, so in went a spare into #1. All the others cleaned up and looked like new, so in they went with a quick spray of WD-40 to be sure. I always clean up the top of the plug with some sandpaper too, making sure the contact is good.
I also picked up a carbon coil cover, which will go on as the stock one had been lost.
It fired up like a champ, and no more miss after 500kms of driving. I'm pretty sure the boot was the issue, with the chewed up bit opening up under enough heat for the spark to jump. The rat junk surely didn't help either!
Whilst at it, I swapped the Pod filter out for the stock airbox with a new element. While the pod sounds good to the Fast and Furious generation, as a daily driver I prefer the minimal induction noise from the stock setup, with no noticeable drop in performance.
Also I put some rubber on the mount for the AVCR solenoid, as the solenoid ticking under boost was quite noticeable once the stock airbox was back on.