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Home >> Daihatsu >> 1988 >> Charade CSX, G100 >> Repair and Diagnosis >> Engine Performance >> System >> Fuel Injection System >> Testing >> Fuel Pump
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Fuel Pump

  1. Connect Special Connector (09991-87702-000) to check terminal. Short terminal "F" (WHT/BLK) with ground terminal (BLK). See Fig 1 . Set ignition switch to "ON" position. Check that a fuel-flowing sound is emitted from around pressure regulator.
  2. If not pressure is applied, check following parts: fusible link, ignition switch, fuse, main relay, fuel pump relay, fuel pump or wiring connections. to check fuel pressure, check for battery voltage or 12 volts or more.
  3. Disconnect cable from negative terminal of battery. Place a container or cloth under fuel filter. Loosen union bolt slowly and pull it out.
    CAUTION: Fuel in fuel pipe is pressurized to 36.3 psi (2.55 kg/cm2 ). Remove union bolt slowly, fuel may be sprayed.
  4. Install a pressure gauge in-line between fuel line and fuel filter. With Special Connector still connected to check terminal, short terminal "F" with ground terminal. See Fig 1 . Reconnect cable to negative terminal of battery. Turn on ignition. Read fuel pressure. It should be 33-40 psi (2.3-2.8 kg/cm2 ).
    Fig 1: Jumping Terminals of Special Connector
    G93472Courtesy of DAIHATSU MOTORS CO. LTD.
  5. If fuel pressure exceeds specified pressure, check following items and repair as necessary:
    • Fuel return hose and/or pipe for restriction or damage.
    • Rubber hose connected between pressure regulator and surge tank for restriction.
    • If previous two items are ok, replace pressure regulator.
  6. If fuel pressure is less than specification, check following items and replace if necessary:
    • Fuel hose and/or pipe for restrictions, damage or leakage.
    • Fuel filter for restrictions.
    • Fuel pump.
    • Pressure regulator.
  7. Read fuel pressure 3 minutes after ignition is turned off. Pressure should be no less than 25.6 psi (1.8 kg/cm2 D). If pressure is less than specified, check following parts: injector, cold start injector, pressure regulator, leakage of fuel hose and/or pipe, and fuel pump.
  8. Remove special connector from check terminal. Attach check terminal cap. With engine warm, measure fuel pressure with engine idling. It should be 21.3-28.4 psi (1.5-2.0 kg/cm2 ).
  9. If fuel pressure exceeds specifications, check vacuum sensing hose system connected to pressure regulator for restriction. Repair it as required. If system exhibits no abnormality, replace pressure regulator.
  10. After completion of check, disconnect cable from negative terminal to battery. Remove fuel pressure gauge by loosening union bolt. Use a cloth to prevent fuel from splashing. Install fuel hose to fuel filter using new gaskets. Start engine and check for leaks.
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