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Deceleration Fuel Cut-Off (Digifant II)

DIGIFANT II

Deceleration Fuel Cut-off - Checking

Note: It is possible to check the deceleration fuel cut-off function using the full throttle switch because the full throttle and idle switch are wired in parallel and connected to the Digifant E.C.U. by the same wires.

Requirements

- Engine oil temperature at least 80°C (176°F).
- Coolant temperature sensor and wiring OK.
- Throttle switches and wiring OK.
- VW engine tester 1367 connected.
- Start the engine and raise speed to a minimum of 2400 RPM four times, letting the throttle close each time,



- With engine idling, close throttle switch with thumb (1).



- While holding full throttle switch closed, SLOWLY open the throttle with a screwdriver (2) to increase engine speed.
- At approx. 2200 - 2700 RPM, the injection will be cut off and RPM will drop.
- At approx. 1300 - 1800 RPM, the injection will re-activate and RPM will rise.
- This cycle will continue as long as you try to hold the RPM steady at 2700 RPM.

If the cycle does not occur,

- Replace the Digifant E.C.U.