Suzuki 2007 XL7, Service Manual

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Fuel System: 1G-5
On-Board Refueling Vapor Recovery (ORVR)
System
The on-board refueling vapor recovery (ORVR) system
is an on-board vehicle system to recover fuel vapors
during the vehicle refueling operation. The flow of liquid
fuel down to the fuel tank filler neck provides a liquid
seal. The purpose of ORVR is to prevent refueling vapor
from exiting the fuel tank filler neck. The ORVR
components are listed below, with a brief description of
their operation:
• The fuel tank—The fuel tank contains two modular
fuel sender assemblies.
• The fuel filler pipe—The fuel filler pipe carries fuel
from the fuel nozzle to the fuel tank.
• The evaporative emission (EVAP) canister—The
EVAP canister receives refueling vapor from the fuel
system, stores the vapor, and releases the vapor to
the engine upon demand.
• The vapor lines—The vapor lines transport fuel vapor
from the tank assembly to the EVAP canister.
• The check valve—The check valve limits fuel spit-
back from the fuel tank during the refueling operation
by allowing fuel flow only into the fuel tank. The check
valve is located at the bottom of the fuel filler pipe.
• The modular fuel sender assembly—The modular fuel
sender assembly pumps fuel to the engine from the
fuel tank.
• The fuel tank pressure (FTP) sensor is located on top
of the modular fuel sender assembly.
• The FLVV—The FLVV acts as a shut-off valve. The
FLVV is located in the modular fuel sender assembly.
This valve has the following functions:
– Controlling the fuel tank fill level by closing the
primary vent from the fuel tank
– Preventing fuel from exiting the fuel tank via the
vapor line to the canister
– Providing fuel spillage protection in the event of a
vehicle rollover by closing the vapor path from the
tank to the engine
• The pressure vacuum relief valve—The pressure
vacuum relief valve provides venting of excessive fuel
tank pressure and vacuum. The valve is located in the
fuel fill cap.
• The vapor recirculation line—The vapor recirculation
line is used to transport vapor from the fuel tank to the
top of the fill pipe during refueling to reduce vapor
loading to the EVAP canister.
EVAP Lines and Hoses
The EVAP line extends from the fuel tank vent valve to
the EVAP canister and into the engine compartment.
The EVAP line is made of nylon and connects to the
EVAP canister with a quick connect fitting.
Fuel Rail
The fuel rail consists of 3 parts:
• The pipe that carries fuel to each injector
• The fuel pressure test port
• Six individual fuel injectors
The fuel rail is mounted on the intake manifold and
distributes the fuel to each cylinder through the individual
injectors.
Fuel Injectors
The fuel injector is a solenoid device that is controlled by
the ECM. When the ECM energizes the injector coil (4),
a normally closed ball valve (1) opens, allowing the fuel
to flow past a director plate (3) to the injector outlet. The
director plate has holes that control the fuel flow,
generating a dual conical spray pattern of finely
atomized fuel at the injector outlet (2). The fuel from the
outlet is directed at both of the intake valves, causing the
fuel to become further vaporized before entering the
combustion chamber.
The fuel injectors will cause various driveability
conditions if the following conditions occur:
• If the injectors will not open
• If the injectors are stuck open
• If the injectors are leaking
• If the injectors have a low coil resistance