PleasureCraft Engine Group 5.0L, Diagnostic Manual

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7 - 32 Symptoms 5.0/5.7/6.0/8.1L
MEFI 4 - PCM
Fuel Injector Balance Test
Step Action Value Yes No
1. Turn the ignition “OFF.”
2. Connect the J 39021 Fuel Injector Tester, the
J39021-303 Injector Harness Connector (if needed)
and the J 39021-210 Injector Switch Box to a
fuel injector.
3. Set the Amperage Supply Selector Switch on the Fuel
Injector Tester to the “Balance Test” 0.5-2.5 amp position.
4. Select the injector to be tested on the Injector Switch
Box.
5. Ignition “ON,” engine “OFF.”
6. Use a scan tool in order to pressurize the fuel system.
7. Record the fuel pressure indicated by the fuel pressure
gauge after the fuel pressure stabilizes. This is the 1st
pressure reading.
8. Energize the fuel injector by depressing the “Push to
Start Test” Button on the Fuel Injector Tester.
7
9. Record the fuel pressure indicated by the fuel pressure
gauge after the fuel pressure gauge needle has
stopped moving. This is the 2nd pressure reading.
10. Repeat Steps 4 through 9 for each fuel injector.
11. Subtract the 2nd pressure reading from the 1st
pressure reading for one fuel injector. The result is the
pressure drop value.
12. Obtain a pressure drop value for each fuel injector.
13. Add all of the individual pressure drop values. This is
the total pressure drop.
14. Divide the total pressure drip by the number of fuel
injectors. This is the average pressure drop.
Does any fuel injector have a pressure drop value that is Review
either higher than the average pressure drop or lower 10 kPa
Symptoms
than the average pressure drop by the specifi ed amount? (1.5 psi) Go to Step 8 Section
Notice: Do Not repeat any portion of this test before
running the engine in order to prevent the engine from
fl ooding.
8
Re-test any fuel injector that does not meet the
specifi cation. Refer to the procedure in Step 7.
Does any fuel injector still have a pressure drop value that Review
is either higher than the average pressure drop or lower 10 kPa
Symptoms
than the average pressure drop by the specifi ed amount? (1.5 psi) Go to Step 9 Section
Replace the faulty fuel injector(s). Refer to the “Fuel
9
Injector” portion of the Fuel Metering section.
Is the action complete? — Go to Step 10 —