I had a similar high fuel consumption (4.5km/ltr) on my 1998 4cyl Accord and after much effort to correct the problem in the fuel injection/ignition system, I discovered the problem was a torn inlet maniflold gasket. Up to now I cannot explain the science of it, but once the gasket was found torn and duely replaced, the problem ceased. I will therefore urge you to check the air inlet manifold sytem carefully for possible tears and leaks.
If you fiind this to be the problem, pls let me know.
May, 24, 2012 AT 2:12 PM
Thanks so much for this answer, because my honda has been killing my wallet. I have done everything form replacing the nozzles to changing the basketlike exhaust thingy just beneath the driver's seat. I hope I can effectively pass on this information to my mechanic.