1387 / 1525
5
4 PL FUEL SYSTEM
The fuel system consists of :
1.
Fuel tank assembly
2.
Electric intank fuel pump with in built pressure
regulator
3.
Fuel level gauge (tank unit)
4.
Fuel filter
5.
Fuel filler cap
6.
Fuel hoses, fuel lines and fuel rail (i.e. delivery and
vapour lines)
The evaporative emission system consists of :
a) Tank pressure valve
b) Canister purge valve
c) Carbon canister
d) Restrictor
e) Vapour separator
GENERAL OPERATION OF EVAPORATIVE EMISSION
SYSTEM:
The systemoperateswhenoutside temperature is higher,
after the vehicle has been parked / standstill
for a long time, the fuel temperature increases andbrings
about a pressure rise inside the tank.This
increasemay occur withmedium - low fuel levels or with
the tank full condition.
During tank refilling, the pressure inside is more or less
same as atmosphere pressure.The breather port
on fuel tank is connected to the breather port on filler
neckwhich allows tank breathing during fuel filling.
When the tank is completely filled, there is small pocket
of air provided for efficient operation of the
evaporative control systemwhen the vehicle is running.
When the fuel filler cap is closed, it seals the system, the
vapours generated inside the tank (with vehiclemoving
or while parked) build up due to fuel volatility, and tank
internal pressure also builds up until the tank pressure
valve opening level is exceeded.
When the engine is inoperative, (i.e. while parked), fuel
vapour generated inside the fuel tank due to fuel volality
are absorbed and stored in the canister.When the engine
is running, the fuel vapours absorbed in the canister are
purged into intakemanifold through canister purge valve
operated by the ECU.
Warning :
l
Before performing the following operation, release
the fuel pressure from the fuel system to reduce the
possibility of injury or fire.
l
While removing the fuel tank fromthe vehicle, keep
sparks, cigarettes and open flames away from it.
l
Before repairing fuel tank assembly, clean it
thoroughly.
l
Disconnect negative cable terminal at battery.
l
Always wear safety glasses.