maybe wrong fuel (try shell v-power) or a-brand fuel and try some
fuelsystem cleaner
check the fuel filter too, it needs replacing after 100.000 km's
a small gap in the air intake circuit can do strange things too and
a dirty egr-valve can also be the cause

try a honda dealer ,in the netherlands they are not that expensive and very
helpful
maybe that costs you labour but that's most of the times cheaper then
just changing parts on luck
are you using the car for short (less then 10km) distances only ?

marcel

"Power loss" is a bit of a short description.
When does it appear? Low revs? High revs? Both cold and warm engine?
Just changing things randomly is not gonna help, or you must be very lucky.
I even think that fuel is not the issue, since most engines are designed to
run on far worse fuel then we can buy in western countries.

K.