5.18.2. Check of pressure in an engine power supply system

The main indicator of serviceability of a power supply system of the engine is fuel pressure in a fuel stage.
With an insufficient pressure of fuel are possible:
– unstable operation of the engine;
– engine stop idling;
– the lowered frequency of rotation of a bent shaft idling;
– insufficient acceleration performance of the car (the engine does not develop full capacity);
– failures in operation of the engine at the movement of the car.
For a start we recommend to check reliability of electric contacts in blocks of plaits of wires of ESUD which are responsible for fuel supply (the module of the fuel pump, a nozzle, the fuel relay and the corresponding safety locks).
Fuel pressure in a power supply system is checked by means of the professional manometer and a hose with the original union for connection to the valve located on a fuel stage.
1. Include ignition and listen: within several seconds you have to hear a sound of work of an electrogasoline pump. If it it is not heard, check an electric power-supply circuit of an electrogasoline pump.

If you included ignition three times without attempt of launch of the engine, once again the electrogasoline pump will not join that is not a malfunction sign. It will join along with the beginning of launch of the engine a starter.

2. Reduce pressure in a power supply system (see. "Pressure decrease of fuel in an engine power supply system").
3. Turn off a protective cap of the union for control of pressure of fuel at an end face of a fuel stage. Pay attention that in a cap the sealing ring is established. If the ring is torn or lost elasticity, replace it or entirely a cap.

For descriptive reasons work is shown at the removed decorative casing of the engine.

Good advice
If there is no opportunity to use the professional manometer, use the ordinary manometer with a hose and a collar. The manometer has to be with a measurement scale no more than 1000 kPa (10 kgfs/cm2) and at the cost of division no more than 20 kPa (0,2 kgfs/cm2). Pay attention to reliable connection (zavaltsovka) of the manometer and a hose.

4. By means of a metal protective cap of the gate of the tire turn out a zolotnik (same, as in the tire) …

At a reversing of a zolotnik a small amount of fuel therefore previously enclose rags under the union can flow out.

5. … also take out it from the union.
6. Connect to the union a hose with the manometer. Fix a hose on the union by a collar and check reliability of its fastening. Launch the engine and check pressure on the manometer. It has to make 380–400 kPa (3,8–4,0 kgfs/cm2).

The following reasons of pressure decrease are possible:
– the fuel pressure regulator is faulty;
– the fuel filter of thin cleaning or the filter of a fuel receiver is littered;
– the electrogasoline pump is faulty.
7. Stop the engine and reduce pressure in a power supply system (see. "Pressure decrease of fuel in an engine power supply system").
8. Disconnect the manometer from the union of control of pressure, screw a zolotnik in the union and install a protective cap on the union.