This guide is intended to roughly define the steps to setup and tune engine fueling. Tuners will have their own preferred methods and techniques but should read this guide to at least have an understanding of the order in which fuel setting must be adjusted.

 

The way in which fuel is setup and tuned varies depending on how the ECU is setup, this is mostly governed by the Fuel Equation Mode used.

 

All Fuel Tuning Modes

·Check and double check that all important fuel and engine configuration settings are correct, changing some settings later could result in a full retune being required.

·Check all fuel correction tables are off, zeroed or set to known values before starting tuning, it is ideal to tune with no influence from these tables then introduce them later.

·Set the AFR/Lambda Target Table values correctly.

 

Traditional Fuel Equation Mode

1.If Charge Temperature Correction is enabled, then the Charge Temperature Approximation Table must be configured before tuning, changing this table later will require retuning of the Fuel Table.

2.An important step is to get a good range of Fuel Table numbers, this involves selecting a suitable Master Fuel value. The aim is to get a good span of numbers across the fuel table to prevent running out of adjustment later.

1.Set the Master Fuel Trim to 0%.

2.The aim is to run the engine at mid RPM/load and get fuel table numbers of around 50. If the numbers are too low, then reduce Master Fuel, likewise if the Fuel Table numbers are too high, increase Master Fuel.

3.Tune the Fuel Table at idle and make sure the numbers have useable resolution. If the numbers are too small, then a lower Master Fuel is required. A typical idle number is around 20-30.

4.If possible check at full power that the Fuel Table numbers do not get too high. A typical full power number is around 75-85.

3.Tune the Fuel Table cells as normal.

 

Modelled (and Multi Fuel) Fuel Equation Mode

Note: Refer HERE for a more detailed Multi Fuel Setup and Tuning Guide

 

1.Modelled Fuel Equation Mode depends critically on all fuel and injector characteristic information being correct. Some parts of the modelled fuel calculation will not deliver the desired result if these numbers are wrong. Do not guess at these numbers, contact your Link dealer for further advice if required.

2.Prior to tuning, ensure the Charge Temperature Approximation Table is configured correctly, changing this table later will require retuning of the Fuel (VE) Table.

3.Ensure Fuel Pressure and Fuel Temperature is stable. Confirm that the Base Fuel Pressure setting is correct and that the fuel system maintains this pressure over the entire operating range (MAP referenced system), if this setting does not match the fuel pressure on the engine then the ECU will not correctly calculate the actual injector flow.

4.Before final tuning can be completed, the Fuel Charge Cooling Coefficient must be set correctly. This can not be adjusted once tuning is complete as it will require retuning of the Fuel (VE) Table.

5.Tune the Fuel (VE) Table cells as normal.