Mazda 626

1991-1998 of release

Repair and car operation

Mazda 626

+ 1. Maintenance instruction
+ 2. Maintenance
+ 3. Engines
+ 4. Heating and ventilation
- 5. Fuel system
   + 5.1. Nikki 30/34 carburetor
   + 5.2. Power supply system (l engines 1,6 and 1,8)
   - 5.3. Power supply system (l engines 2,0 and 2,5)
      5.3.1. Introduction
      5.3.2. Technical characteristics
      5.3.3. Pressure dumping in fuel system
      5.3.4. Fuel pump and fuel pressure
      5.3.5. Fuel tubes and connections of tubes
      5.3.6. Sensor of a measuring instrument of level of fuel
      5.3.7. Fuel tank
      5.3.8. Casing of the air filter
      5.3.9. Accelerator rope
      5.3.10. Electronic system of injection of fuel
      5.3.11. Butterfly valve casing
      5.3.12. Regulator of pressure of fuel
      5.3.13. Fuel highway and injectors
+ 6. Exhaust system
+ 7. Transmissions
+ 8. Coupling and semi-axes
+ 9. Brake system
+ 10. Running gear
+ 11. Body
+ 12. Electric equipment
+ 13. Electroschemes
+ 14. Good advice

5.3.4. Fuel pump and fuel pressure


Set for check of the majority of fuel systems

General check

1. Check, that in a fuel tank there was fuel enough.
2. Check, whether the fuel pump works. Include ignition and listen to a mouth of a fuel tank, you should hear a short buzzing sound. If the pump does not work, check an electric chain of the pump.
3. In the Probe models first of all check the switch with a delay mechanism, located in a luggage compartment.

Pressure check

1. Disconnect the working mechanism of system control cruise.
2. Connect a pressure measuring instrument to a hose conducting from the fuel filter (4-cylinder models) or between fuel tubes.
3. Include ignition (the engine does not work, central air of air is disconnected). The fuel pump should turn on approximately for two seconds. Pressure in system should increase and keep on one mark.
4. Get the engine and warm up it to normal temperature. Write down indications of a measuring instrument and compare them to technical requirements. Disconnect a vacuum hose from a regulator of pressure of fuel – pressure should instantly will increase. If you received all necessary results, means, the system functions correctly.
5. If after a detachment of a vacuum hose pressure in system did not raise, increase a razryazheniye in a regulator of pressure having connected to it the vacuum pump. If pressure of fuel went down, means, the vacuum does not move in a regulator through a vacuum hose. If pressure did not go down, replace a regulator of pressure of fuel.
6. If pressure of fuel does not correspond to technical requirements:
а) Pressure too high. Check, whether the vacuum in a regulator of pressure of fuel moves. If the vacuum moves, check, whether the hose or a tube of return of fuel is littered. If the hose is not littered and not передавлен, replace a regulator.
б) Pressure too low. Replace the fuel filter. If pressure did not raise, get the engine and block a hose of return of fuel. If pressure increases above 47 psi, replace a regulator.
в) If pressure still low, check, whether the injector or injectors proceeds. Check serviceability of the fuel pump.

Check of an electric chain of the fuel pump

1. If the pump does not work, check its safety lock in the block of fuses. If necessary replace a safety lock.
Models of 1993-1997
2. If the pump still does not work, uncover the block of signaling located in office of the engine and close a crossing point contacts of the fuel pump and grounding. The fuel pump should earn.
Models of 1998
3. If the pump still does not work, remove the pump relay from the relay block. Close a crossing point contacts of 30 and 87th nest of the relay.
All models
4. If the pump does not turn on, check, whether tension on pump contacts moves, and whether there is no gap in a chain of grounding of the pump. If check showed positive results, replace the pump.

Removal and installation

1. Disconnect a wire of the minus plug of the accumulator.
2. Lower pressure in system.
3. Remove a fuel tank.
4. Disconnect wires and fuel tubes from the pump.
5. Remove a lock ring of the pump.
6. Get the pump from a fuel tank.
7. Weaken clips of a hose and disconnect it from the pump.
8. Disconnect the socket from the fuel pump.
9. Remove a lock ring and the filter.
10. Disconnect the pump from its arm.
11. Installation is carried out upside-down removals.