If engine power is decreasing, increased noise is observed, or a whining sound is heard periodically when the fuel pump is running, the fuel pump is most likely faulty.
Preliminarily check the pressure in the fuel supply system as follows.
Check the serviceability of the fuel pressure regulator (see below "Replacing the Renault Logan Pressure Regulator").
If the system pressure is less than 250 kPa (2.5 kgf/cm), replace the fuel filter.
If this does not help, remove the pump and clean the fuel pickup screen.
If the pressure still does not increase, the fuel pump must be replaced.
Replacing the Fuel Pump
You will need a flat-blade screwdriver.
Relieve the pressure in the fuel system (see "Renault Logan Fuel System Pressure").
Disconnect the negative battery terminal.
Remove the rear seat cushion.
Pry off the plastic cover with a screwdriver. Fuel pump cover
Remove the plastic fuel pump cover
Press the latch and disconnect the wiring harness connector from the fuel pump module.
Disconnect the high-pressure fuel line and the fuel return line from the pump fittings.
Unscrew the fuel pump module retaining ring by installing the pliers and lever as shown in the photo and remove the ring.
Carefully remove the fuel pump module and drain the fuel into a prepared container.
When removing the fuel module, tilt it slightly and pull it out very carefully to avoid damaging the fuel gauge sensor float.
Remove the sealing gasket.
Be sure to replace the gasket if it is torn or severely compressed.
Disconnect the fuel level sensor connector.
Pinch the plastic clips and remove the fuel pump assembly from the collection cup.
Remove the fuel pickup filter from the pump.
Use a screwdriver to release the clips and remove the upper part of the fuel pump assembly, disconnecting the wiring connectors from the pump.
Remove the pump from the module housing.
Disconnect the fuel hose from the pump.
Reassemble the fuel pump module in the reverse order of disassembly.
Install the parts in the reverse order of removal.
Make sure the marks on the fuel tank and module housing align when installing the module.
Replacing the Fuel Pressure Regulator
Serviceability Regulator failure is determined with the engine running by measuring the fuel pressure in the injector rail (see "Renault Logan Fuel System Pressure").
If the pressure is below normal, but the other system components are functioning properly, the regulator is faulty.
It must be replaced, as it cannot be repaired.
The fuel pressure regulator is installed in the fuel pump module.
Remove the fuel pump module (see "Replacing the Fuel Pump on Renault Logan").
Disconnect the fuel level sensor wiring harness connector.
Pinch the clips and remove the fuel pump assembly from the reservoir.
Remove the rubber sealing ring
Remove the thrust washer
Remove the spring
Press the latch and remove the fuel pressure regulator fitting from its seat in the module cover.
Press the latch and disconnect the ground wire.
Remove the fuel pressure regulator.
Reinstall the parts in the reverse order of removal.