at what revs does injector cut happen on deceleration, then cut back in to avoid stalling ?

[Steptoe's photos]

One of efi secrets on fuel saving over old school carburettor is that on deceleration, throttle closed, the ECU/ECM will cut the injectors from squirting fuel.  This will not happen in Angel Gear, for it is the wheels / transmiison that keeps the engine turning over. Has anyone worked out, or know at what revs this injector generally happens on our EJ cars?

[GeneralDisorder]

Overrun fuel cut deactivation is typically a table based on coolant temp. Minimum RPM at full temp is usually somewhere between 1200 and 1800 rpm at full temp. Above that RPM any throttle position under about 1.5% activates fuel cut. There is typically a large timing retard that occurs during activation and deactivation to smooth the transition. 

GD

[Steptoe's photos]

Now, that is some pretty handy info GD. If I then asked if you know more specifics of EJ202 1999 era, get any closer to that sweet rev moment? I am thinking, if I pick a lower gear , to get higher revs, above 1800 -2000, on decel runs, I may achieve better economy ....though am real happy with it's long term average of 7.75 litres per 100 km (62.5 miles) And, the tinkerer I can be, thinking if I rigged a NOID light in cabin, powered by the main relay circuit (same as the injectors) then a wire off an injectors pulse wire _ I could watch when the noid light goes out - should indicate when the OFC is activated  or, I might just upset the ECU

Edited July 8, 2023 by Steptoe's photos

[GeneralDisorder]

You would have to test it. These are general principles used by all fuel injection but the subtleties of individual implementations are not something I have tested or disassembled the code looking for.

GD