Checking the fuel pressure in the fuel rail of the engine is only possible with a pressure gauge with a set of adapters for connecting to the fuel pipeline.
1. Turn on the ignition and listen: within a few seconds you should hear the sound of the electric fuel pump. If it is not audible, check the electrical supply circuit of the electric fuel pump.
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 serviceable 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 procedure for checking fuel pressure is described in Sec. 5 «Engine» (see «Checking the pressure in the engine power system»). With the engine idling, the pressure in the fuel line should be about 3 kgf / cm2 (approximately 2.65 kgf/cm2).
The following reasons for pressure drop are possible:
- clogged fuel filter;
- faulty fuel pump. A fuel pressure regulator is built into the fuel pump module, so the cause of a drop in fuel pressure, in addition to a malfunction of the pump itself, may be a malfunction of the regulator. In both cases, the fuel pump must be removed from the vehicle for repair.
You can find ways to troubleshoot these problems in Sect. «Engine» (see «Supply system»).