Dan, I wasnt refering to you there mate.
ITRHondaboy, ok, no offence taken then. Im not trolling.
BenTaylor....recirculating air that is trapped is not the same as a leak. You dont need maths or physics to explain airflow or fuel mass? What would you use then??
And Ben & the others who confirm the Nissan ECU cuts fuel on the overrun, then should agree it shouldnt massively overfuel on throttle closure, except just for a tiny fraction of a second until it drops to cut-off or the throttle is opened again.
This is really getting boring now cos no one except us wants to know why it does this!!!!!!