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Test 2: Fuel Injectors

  1. Check for fuel delivery at injectors. If one or more injectors are not operating correctly, place finger on injector and feel for injector pulses (vibration).
  2. If no pulses are detected, check power supply to injectors. Also check injector resistance. If test is not okay, check wiring for shorts, opens or poor connections. Repair as needed. If wiring is okay, replace defective fuel injectors.
  3. If previous test are okay, connect volt/ohmmeter between wire No. 87 (Red/Blue) on relay No. 2 and ground (relay plugged in). Meter should read battery voltage. If not, go to TEST 3: MOTRONIC CONTROL UNIT  .
  4. If voltage is correct, check activation of injectors. If test value is not okay, replace MCU.
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