A while back I had a new HBV and new Coil Pack fiited, coil pack was fitted to cure a miss which was present all the time even from cold, and the HBV was fitted to cure an on going niggly water leak.
Car has run like a dream and lost no water at all since the parts were replaced almost 3 months ago.
But over the year the car has had more use than the usual sort journeys it has where it gets warm/hot and then not used for a few days. On the longer runs and then satin trafic the heat cycle through the engine seems to bring on a misfire not unlike the failing coilpack isue, misses at all speeds under load and down on power. Leave the car overnight and use the car again on short journeys there is no misfire at all. Then if out and about for say half and hour or more the misfire returns.
The other thing is that while the car ins warming up it now takes longer to feel the warmth to come through to clear the screen, hoping the heater matrix hasnt filled up with crap since the HBV was fitted as it warmed though with in half a mile or so before it was changed.