Checking the fuel pressure in the engine fuel rail is only possible if you have a pressure gauge with a set of adapters for connection to the fuel line.
1. Turn on the ignition and listen: within a few seconds you should hear the sound of the electric fuel pump. If you do not hear it, check the electric fuel pump power circuit.
Attention! Keep in mind that the electric fuel pump does not turn on if there is pressure in the fuel supply system. In other words, if you previously turned on the ignition and tried to start the engine, then a working electric fuel pump should have created pressure in the system and its failure to turn on in this case is not a malfunction.
2. The fuel pressure check procedure is described in Section 5 "Engine" (cm. "Checking the pressure in the engine fuel system"). When the engine is idling, the pressure in the fuel line should be about 3 kgf/cm² (approximately 2.65 kgf/cm²).
The following are possible reasons for the decrease in pressure:
- clogged fuel filter;
- faulty fuel pump. The fuel pump module has a built-in fuel pressure regulator, so the cause of the drop in fuel pressure, in addition to the malfunction of the pump itself, may also be a malfunction of the regulator. In both cases, the fuel pump must be removed from the car for repair.
You will find methods for troubleshooting these problems in the section. "Engine" (cm. "Power supply system").