Fuel Management

Fuel system basics

THE best outline about the fuel system can be found in the following thread.

Flexfuel

The ECU will do automatic mass fuel flow (mff) compensation based on ethanol content. It can do this both with a sensor or sensorless.

By default, the calibration is set up to leverage a "manual" ethanol setting (which is what the ED code short circuits for the slider). When configured in automatic mode, the ECU will use algorithmic based flex fuel adaptation. By enabling a sensor (pinned to pin 71 [need to verify]), the ecu will instead use the sensor unless the sensor fails.

Switch to use manual alternative fuel ratio
lc_fac_afu_ratio_man_act - set to [00] to disable

Logical value to indicate AFU sensor configuration
lc_fac_afu_ratio_conf - set to [00] to enable the sensor (not a typo)

It also might be helpful to enable the PID output for e-content (PID 52) Details start on page 23709 of the FR. c_state_srv_1_pid[n][10] is the bit field that includes pid 52.

Port Injection

In some markets, the EA888.3 series of engines are equipped with port direct injection (DI) and multiport injection (MPI). NA cars only include DI. In order to run larger turbos or increase the capability of the fuel system to run alternative fuels (e85) in a performance scenario, the MPI system can be added.

Continental didn't intend to use the MPI system in the way we use it (under full load, at high RPM, with big injectors) so when enabling the native MPI we also must change the logic that controls it. MPI, DI, and the way they work together are dictated through the use of combustion modes (along with other things).

The combustion mode manager receives combustion mode requests from other engine operating managers. In the case of MPI at full load, we'll use the torque manager to define the window(s) where we want MPI to be active.

The torque manager has 6 combustion mode indices that can be controlled and triggered. Each of those combustion mode indices will have min and max RPM, as well as min and max torque tables that will define when that index is targeted. Changing which combustion mode a particular torque index references (and then tuning the max and min tables appropriately) will change whether we're targeting a standard combustion mode or a DI + MPI combustion mode.