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Test 2: Fuel Injectors

  1. Check for fuel delivery at injectors. If one or more injectors are not operating correctly, start engine and check for movement of needles in injectors. Movement can be felt with finger.
  2. If no movement is detected, check the power lines and the coil of the fuel injectors according to the procedures in the BMW TEST KIT, L-JETRONIC PROCEDURES BROCHURE, step 5). See DESCRIPTION  . If test value is incorrect, check wiring for shorts, breaks or poor connections and repair as needed. If wiring is okay, replace defective fuel injectors.
  3. If test value is correct, check power supply to injectors: Connect a voltmeter between wire 87 (Red/Blue) on Relay 2 and ground (relay plugged in). Meter should read battery voltage. If not, go to Test 3 for Motronic Control Unit.
  4. If voltage is correct, check activation of the injectors. See BMW TEST KIT, L-JETRONIC PROCEDURES BROCHURE, step 2). See DESCRIPTION  . If test value is incorrect, replace MCU.
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