Overrun Fuel Cut

This Function allows for the shutdown of the injectors during overrun.

Function Enable

OFF = Function is switched off and the selected output channels are deallocated.

ON = Function is switched on

Function Type

There is one mode are available.

  • ORFC Mode 1

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ORFC Setup

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ORFC TP/PP Select

Selects which input is used to control the ORFC

0: Throttle Position 1

1: Pedal Position

ORFC TP/PP Threshold

When the TPS 1 or PPS value is below this setting the Over Run Fuel Cut can become active.

** Follows ORFC TP/PP Select

Post Start Delay

Delay after the engine has been started before ORFC can become active

Ignition Retard

Ignition Retard from the total ignition advance when ORFC is active

Ignition Recovery rate

Rate which the ignition Overrun Fuel Cut Ignition Retard is decayed to 0 once the engine has recovered.

Typical : 10 deg / sec

Engine Temperature Lockout

Engine Temperature that must be exceeded before ORFC can become active

Speed Channel

Used to define how the “Speed Lockout” is used.  

0: OFF

1: Drive Speed

2: Ground Speed

3: Drive Speed Front L

4: Drive Speed Front R

5: Drive Speed Rear L

6: Drive Speed Rear R

7: Undriven Speed Front L

8: Undriven Speed Front R

9: Undriven Speed Rear L

10: Undriven Speed Rear R

11: Front Axle Speed

12: Rear  Axle Speed

13: Vehicle Speed

14: Engine Speed

15: Input Shaft Speed

16: Output Shaft Speed

** Speed inputs must be defined and properly calibrated under “Input Setup”

Speed Lockout Range Lo

Speed below which ORFC cannot become active\

Speed Lockout Range Hi

Speed above which ORFC cannot become active\

Speed Range Hysteresis

Hysteresis to prevent Overrun Fuel Cut becoming active on the threshold of a speed lockout value.

Example : A speed Lockout Range Hi setting of 60 and a Speed Range Hysteresis setting of 5 will not allow Overrun Fuel Cut to become active until Speed has reduced to 55 after being over 60.

ORFC Cut Ramp Time

Used to progressively increase the cut from 0% to 100% over the specified time.

Allows for a smoother transition into the Fuel Cut.

ORFC On DelayTable

Once all ORFC conditions are met, this look up table tells the ECU how long to delay fuel cut off for in seconds

** ORFC will only become active once all conditions are met, including exceeding the Enable RPM.

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Recover RPM Table

This 3D capable look up table tells the ECU at what RPM to switch off the ORFC fuel cut off

** ORFC will only become active once all conditions are met, including exceeding the Enable RPM.

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Above example shows uses one axis using Engine RPM and one for Engine Speed Rate of Change (dRPM)