Scooby Jonni

My car has started to misfire when on boost. It used to cut in hard at about 0.8bar then the next day it was at happening at 0.3bar, the next day it went away completely. Now its not too bad.. i can just hear a bit of misfire when going up through the revs.

I've looked at all the plugs (bkr7e) and they all look fine.. just a bit of soot from where it has been running a little rich. I cleaned this off and regapped them to 0.7mm to to no avail. The previous owner said he has changed the HT leads so they should be fine.

This leaves me thinking that it must be the coil pack. I'm just wondering if there is anything else I can check before ordering a new one? I did some logs off all the sensor and the MAF & MAP are ok. The only thing that seemed wrong was ARF going up a bit during the misfire.

My car is a V3 STI RA with standard turbo/injectors, chipped ECU, Walbro 255, FMIC and full breathing mods. I first noticed the problem while on a track. The ECU has no error codes.

Thanks for any help you can offer.