Honda visit would be a first move I think.
If you want to do it yourself then you definitely need a code reader.
For a trip to Aus I bought a $3000 Jazz, that developed an intermittent problem with loss of power and engine cut out at random times.
After failed fault diagnosis at auto electricians, I bought a scanner and car workshop manual and eventually chased the fault down to an intermittent faulty computer. Bought a second hand one and that fixed the problem.
In the meantime I had replaced the plugs and leads, ERG, other sensors, fuel filter etc.
So get a code scanner and PDF manual from the internet.
A tip that it could be the computer (if the problem is intermittent) is that no codes are present when the engine stops.
If you need to replace the computer, you need to remove the airbag therefore have to visit Honda to reset the airbag warning light.