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Home >> Chevrolet >> 1998 >> Camaro Base, 2D Convertible, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - System & Component Tests - 3.8L >> Fuel System >> Engine Control System - System & Component Tests - 3.8L >> Fuel Injector Balance Test
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Fuel Injector Balance Test

  1. If powertrain OBD system check has been performed, go to next step. If powertrain OBD system check has not been performed, perform powertrain OBD system check. See POWERTRAIN OBD SYSTEM CHECK in TESTS W/CODES - 3.8L article.
  2. If fuel injector coil test has been performed, go to next step. If fuel injector coil test has not been performed, perform fuel injector coil test. See INJECTOR COIL TEST - ECT BETWEEN 50-95°F.
  3. If engine coolant temperature is below 201°F (94°C), go to step 5). If engine coolant temperature is above 201°F (94°C), go to next step.
  4. Allow engine to cool until coolant temperature is below 210°F (94°C), then go to next step.
  5. Install fuel pressure gauge. Turn ignition switch to RUN position then to LOCK position. Bleed air from fuel pressure gauge. Using scan tool, energize fuel pump. If fuel pressure reading is 48-55 psi (3.4-3.9 kg/cm2 ), go to next step. If fuel pressure reading is not within specification, perform fuel system diagnosis. See BASIC TESTING - 3.8L article.
  6. Turn fuel pump off. Observe fuel pressure gauge. If fuel pressure remains constant, go to next step. If fuel system does not remain constant, perform fuel system diagnosis. See BASIC TESTING - 3.8L article.
    NOTE: Perform step 7) on each injector.
  7. Disconnect fuel injectors harness connector. Using appropriate fuel injector adapter, connect Fuel Injector Tester (J-39021) to fuel injector. Connect fuel injector tester power leads to appropriate battery terminals. Set amperage supply selector switch on fuel injector tester to Balance Test 2.5-amp position. Turn ignition switch to RUN position then to LOCK position. Record fuel pressure reading (first reading). Energize injector by depressing PUSH TO START TEST button on injector tester and hold until fuel pressure gauge stabilizes. Record fuel pressure reading (second reading). Subtract first reading from second reading (this result is pressure drop value). Add pressure drop value for each injector together and divide total by total number of injectors. If any injector's drop value is greater or less than average drop value by 1.5 psi, replace faulty injector(s) as necessary. If no injector's drop value is greater or less than average drop value by 1.5 psi, injector balance test is okay at this time.
WARNING: In order to prevent flooding of cylinder and possible engine damage, relieve fuel pressure before performing injector coil test procedure.
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