2004 V40 1.9t, misfiring on cylinder 1, replaced coils and spark plugs, still misfiring. Clear codes, good until you hammer on the throttle, starts missing intermittently and then constantly when turbo reaches full boost. any help would be great.

 

Possibly leaking injector, if u have good spark plugs and ignition coils.
Try swapping injectors if it is possible...