Regarding fuel wash on shutdown, I don't understand why manufacturers don't design the injectors to shut off immediately when the ignition is cut off. Clearly there is no need for any fuel during those last few revolutions during shutdown, and this should be very easy to program into the ECM. My pickup has a carbon filter to catch vapors coming up the intake before they enter the atmosphere, which seems very silly and unnecessary... if only the injectors could be shut off when fuel is no longer needed.