Complaint: drive characteristic faults, lack of power

• Run engine at idle speed and measure fuel pressure.

  If the measured value is less than the nominal value - 0.2 bar: 

  • Line cross-sections in fuel feed are constricted or fuel filter is clogged,

    or

  • Fuel pump voltage supply is not O.K.: e.g. as a result of high contact resistance (corrosion) in plug connection between wiring harness and fuel pump.

  If the measured value is greater than the nominal value + 0.2 bar: 

  • Turn off engine stop and then observe measured value.
  • If measured value drops to nominal value, then line cross-sections in fuel return are constricted or clogged.
  • Check the fuel lines for kinks.

  If no kinks are visible:

  • Replace return lines

If measured value remains too high, then pressure regulator is in all probability faulty.