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Home >> Mazda >> 2003 >> B2300 Base, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> System Tests >> Fuel Injector Inspection
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Fuel Injector Inspection

  1. Listen For Injector Operation -  Start engine and idle until normal operating temperature is reached. Using a stethoscope (if necessary), listen for "clicking" sound from fuel injectors. If engine will not start, crank engine and listen for "clicking" sound from fuel injectors. If fuel injectors are clicking, go to step  3 . If fuel injectors are not clicking, go to next step.
  2. Check Injector Resistance -  Turn ignition off. Disconnect suspect injector 2-pin harness connector(s). Measure resistance across injector terminals. See FUEL INJECTOR RESISTANCE SPECIFICATIONS  table. If resistance reading is within specification, check injector driver circuits in PCM. If resistance reading is not within specification, replace faulty injector(s). Go to next step.
    FUEL INJECTOR RESISTANCE SPECIFICATIONS

    Engine Ohms
    2.3L 11-13
    3.0L 8.5-15.5
    4.0L 11-18
  3. Check Injectors For Fuel Leakage -  Release fuel pressure. See FUEL PRESSURE RELEASE under FUEL SYSTEM in BASIC DIAGNOSTIC PROCEDURES article. Remove fuel rail assembly from engine. With fuel lines connected to fuel rail assembly. Disconnect Inertia Fuel Shutoff (IFS) switch harness connector. Install fused jumper wire between positive battery terminal and IFS switch harness connector (Pink/Black wire) to energize fuel pump. Observe fuel injectors for leakage. If fuel injectors leak less than one drop within 2 minutes, fuel injectors are okay. If fuel injectors leak more than one drop within 2 minutes, repair or replace as necessary.
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