Note. Before starting work, read the precautions in Section General information and security measures.
Attention! After performing the procedure described below, you will only remove excess pressure from the fuel system. Gasoline will remain in the pipelines. Before disconnecting any fuel hose, take all necessary precautions!
Service valve location (1/1) pressure relief on the fuel line of gasoline engines
1/1 - Service valve; 1/4 - Screw; 2/1 - Casing of the resonator; 17 - Fuel line; 17/1 - Bolts; 17/2 - Fuel supply line; Y62 - Injectors
The main components of the fuel systems of gasoline engines are a fuel tank, a fuel pump with a fuel reserve sensor located inside it, a fuel filter, injectors, a pressure regulator and a set of connecting lines.
When the engine is running, the fuel inside the fuel system path is under pressure, which continues to be maintained for quite a long time after the ignition is turned off. Before disconnecting any of the system components, the pressure on the stroke must be relieved.
The easiest way to relieve pressure in the power system is to start the engine with the fuel pump fuse removed - wait for the engine to stop spontaneously, then, to ensure complete pressure relief, turn it a few more times with the starter. If the engine cannot be started, crank it over with the starter for a few seconds. After completing the procedure, turn off the ignition and replace the removed fuse.
At service stations, the pressure in the fuel system is relieved through a service valve located on the fuel distribution line and operating on the principle of a simple nipple. Wrap the valve with a rag, remove the cap and press the nipple - do not forget to return the cap to its place at the end of the procedure.
Remember that after depressurizing / removing fuel from the power system, it takes a little longer than usual to start the engine - you will have to crank the crankshaft with the starter for several seconds until the pressure in the system is restored and the fuel fills all the fuel lines.