AEM 30-1931 Universal Fuel Ignition Controller 8 Channel - Manual (Page 11)

Page 11
Connect the F/IC to the PC using the supplied USB cable. See Figure 20.
Using the F/IC
The F/IC is a very unique product, capable of precise Fuel and Ignition Control.
However, the F/IC, by d esign, is a “piggyback” engine controller, not a stand-alone
ECU. Because it is a piggyback controller, the F/IC relies heavily on the factory ECU.
As factory ECU’s get more and more complex, it is more difficult to sustain improved
engine performance wi
thout the factory ECU “detuning” the engine. Thus, the key to
using the F/IC is to make it work in harmony with the factory ECU.
Tuning Tips

Tune the F/IC so the factory’s ECU’s closed-loop fuel trims are as close to zero
as possible using the fuel maps.
Change the factory ECU’s closed loop target
AFR using the O2 table. Most factory ECU’s can sense extra fuel and will
promptly adjust the fuel trims to remove the extra fuel. For easy reference, fuel
trims can be monitored with an OBDII scanner or equivalent device. Positive fuel
trims are reduced by adding fuel. Negative fuel trims are reduced by removing
fuel.

Keep it simple. Many times it is not necessary to use every function of the F/IC
to obtain the desired engine performance. If the desired engine performance can
be achieved by adjusting only two maps, use only the two maps. There is no
benefit to adding fuel in one map and removing it in another.

Be conservative when making changes. A small step in the wrong direction is
less likely to damage an engine than a large step in the wrong direction.

Use the Oxygen Sensor functions only when additional closed-loop fuel is
needed.
Absolute Pressure Explained
(Note: The F/IC reads and displays absolute pressure. Please read the
following section before tuning.)
Figure 20. USB Com Cable Connection