The high pressure fuel pump (HPF) is driven by gears from the rear end of the crankshaft.
A mechanical booster pump is also installed in the pump housing, which ensures the suction of fuel from the tank.
Для проверки производительности топливного насоса:
- disconnect the fuel line to the rail;
- we connect a clean hose to the outlet of the high pressure fuel pump;
- insert the other end of the hose into an empty container;
- turn on the starter for 30 seconds and measure the flow of the fuel pump.
The fuel pump flow should be at least 45 ml in 30 seconds at 150 rpm.
If the flow of the fuel pump during the operation of the starter does not correspond to the minimum rate, do the following:
- check the absence of air in the fuel (article - Maintenance of the GAZelle Next fuel system);
- we check the blockage in the inlet fuel line (article - Repair of the GAZelle Next fuel intake).
If the results of these tests are correct, check the resistance of the electronic fuel management system actuator valve:
- we measure the resistance of the control valve of the electronic fuel management system.
The minimum resistance is 5 ohms, if the resistance value is not correct, we replace the valve.
Remove the wire connector.
We unscrew the three valve mounting bolts.
Remove the control valve of the electronic fuel management system by turning it and pulling it out.
The O-ring must be replaced.
We install a new O-ring, lubricating it with clean oil, install the electronic valve by turning it and inserting it inside flush with the seating surface. The tightening torque of the bolts is 7 Nm.
After replacing the control valve, we re-measure the flow of the fuel pump.
If the minimum fuel supply is not correct, we replace the fuel pump and delete the fault codes.
If the engine does not start, you need to check the fuel flow through the fuel return line - this will help identify a problem with the high pressure fuel pump.
A malfunctioning return line valve or fuel pump can cause high fuel consumption through the return line to the high pressure pump.
Remove the quick-release fitting for draining the fuel from the high-pressure pump.
To reduce the risk of fuel leakage from the combined rail / injector drain line, close the flexible fuel return line with the fuel line plug (catalog no. 4918464).
We put a drain hose with a quick-disconnect fitting (No. 4918434), or its equivalent, on the drain pipe of the fuel pump.
Place the end of the fuel drain hose in a measuring jar.
We start the engine and bring it to idle.
When fuel begins to flow into the graduated cylinder, we measure the flow rate in 30 seconds.
The maximum flow rate for 30 seconds at a rated speed of 800 rpm should be 310 milliliters.
Replacing the high pressure fuel pump
Disconnect the negative terminal of the battery. We remove the fuel filter (article - Maintenance of the GAZelle Next fuel system) to improve access. We clean pipelines, fittings from dust and dirt.
We squeeze the clamps and disconnect the tip of the supply pipeline from the pump
We unfasten the holder of the return pipeline and remove the tube from the holder
We squeeze the clamps and disconnect the tip of the return pipeline from the injection pump
We unscrew the mounting bolt of the holder and disconnect the fuel supply pipe to the rail from the bracket
Unscrew the union nut securing the fuel supply pipe to the rail
Disconnect the tube
Press the latch and disconnect the wiring block from the fuel shut-off valve
Unscrew the three bolts securing the injection pump to the cylinder block
We take out the bolts from the holes
We take out the injection pump from the bore (the pump is sealed with a rubber ring, installed with an interference fit).
Installing a new rubber ring on the pump housing
We clean the walls of the hole in the block
Lubricate the O-ring on the pump casing and the walls of the hole in the pump block with clean engine oil.
During the installation process, we make sure that the teeth of the pump gear coincide with the teeth of the pump drive.
Tightening torque of the high pressure fuel pump mounting bolts - 25 Nm.
Tightening torques of unions of fuel pipelines 27 ± 2 Nm