Holley MPI PRO-JECTION Installation Tuning And Troubleshooting Manual page 25

3 - The Advanced Setup parameters should be set at this time. If you plan on using Spark Control, the Spark Control must
be set for the proper ignition type using the F2 key before the engine can be started. Enter into "Advanced Setup" under
the Edit menu and select the proper ignition type. In addition, use the arrow keys to go to the Rev Limit section and the
desired idle setting and enter your desired maximum engine and idle speed. In addition, select a temperature that you
would like to have the engine enter closed loop control mode. Holley has used a value of 110° F in the base maps for
marine use, and 75° F for automotive use. This value can be adjusted up or down depending on where the user wants
the ECU to go into closed loop. If the coolant temp monitored in the Data Monitor screen goes below this value during
operation, the closed loop activation temperature may need to be adjusted down. Use the F4 key to select the proper
number of cylinders for your engine. The other parameters will not need to be set or adjusted at this time. After selecting
the proper map and choosing the proper Advanced Setup parameters, save the PRO-JECTION system map to your
computer using a personally selected file name of up to eight characters under the File menu and re-send the map to the
ECU.
4 - Turn the ignition key to the run position. Leave the ignition key in the run position until the electric fuel pump can be
heard running. The pump will run for about 10 seconds before shutting off. Start the engine and allow the engine to idle.
5 - Allow the engine to warm up before tuning the Injection Volume map. This is a good time to check the return fuel
pressure. Read the value of the fuel return pressure on the gauge previously installed. A return line pressure over 5 psig
when the engine is running indicates that 1) the tubing diameter may be too small or 2) there may be too many bends in
the line or 3) the line is kinked or obstructed. Any high return line pressure condition should be corrected before any
further fuel map tuning is done.
DANGER! RETURN LINE PRESSURE MUST BE LESS THAN 5 PSIG FOR THE DIGITAL PRO-JECTION SYSTEM TO
PROPERLY OPERATE. RETURN LINE PRESSURE OF 5 PSIG OR MORE CAN RESULT IN HARD
STARTING OR A FUEL LEAK. A FUEL LEAK COULD IGNITE RESULTING IN PROPERTY DAMAGE,
SERIOUS INJURY, AND/OR DEATH.
6 - Skip this paragraph and go to paragraph 7 if tuning without an oxygen sensor. Enter "Data Monitor" in the program
software. Watch the Oxygen Voltage value and the Oxy Comp value. If the engine is idling satisfactorily, allow the
engine to reach operating temperature. Now is a good time to verify proper fuel map tuning. If the engine map is too rich
at idle, the Oxy Comp will be displayed with a negative value. If the engine map is too lean at idle, the Oxy Comp will be
displayed with a positive value. The Oxygen Voltage should be rapidly changing between values of 0.1-0.9 volts. This
indicates normal ECU closed loop operation. If the Oxygen Voltage is 0.0, this indicates either an oxygen sensor
problem, a lean condition, or a wiring problem with this circuit. A relatively constant (reading ± 0.2 volts) Oxygen Voltage
and an Oxy Comp value of 0% indicates that the engine is operating in open loop mode. The engine will normally operate
in open loop mode on any startup until the engine reaches the closed loop operating temperature entered in the advance
setup mode. Enter "EEprom Programming" and make the "Graph", "Injection Volume" menu selections. Move the arrow
around the map using the arrow keys until the map arrow is located on the line of current idle speed. Change the
Injection Volume value by pressing F6 or F7 to move the entire Injection Volume line up or down to either give a richer or
leaner fuel mixture at the current idle RPM. Save the map, and send the map to the ECU.
7 - After the engine reaches operating temperature, the warm idle speed must be set. Enter "Advanced Setup" under
"EEprom Programming" and type in the desired warm idle speed of your engine. After saving this value and sending the
map to the ECU, the throttle body curb idle speed must be set. With the engine fully warmed up and the shift lever in
neutral, remove the air cleaner. Connect engine tachometer if engine is not equipped or use RPM reading in the "Data
Monitor" section. Cover the IAC air passage, shown in figure, with your finger. The idle speed should be set to
approximately 50 RPM below the desired idle speed entered in the Advanced Setup. If the engine idle speed is not
correct, adjust idle speed set screw. This adjustment should be made when the engine has reached operating
temperature.
8 - If the idle speed set screw was adjusted in the above step, the Throttle Position Sensor (TPS) will have to be readjusted.
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