Flow chart
"A" assembly: fuel tank unit module with separate fuel filter
"B" assembly: fuel gauge/pump module with integrated fuel filter
(1) fuel pressure regulator
(2) throttle butterfly housing
(3) inlet manifold
(4) canister discharge electrovalve
(5) canister reservoir (active carbon filter)
(6) Petrol breather blow-by pipe system
(7) fuel tank
(8) fuel pump and gauge assembly (submerged in the fuel tank)
(9) fuel supply pipe
(10) fuel return to tank hose
(11) fuel filter
(12) petrol injectors
(13) petrol injector supply rail
(14) valve SCHRADER (according to model)
(15) fuel gauge/pump module with integrated fuel filter
(16) fuel filter
(17) fuel pressure regulator
Special features
- Injection rail without petrol pressure regulator
- Fuel pressure regulator incorporated into the sender unit
- Injection rail without fuel return
WarningAfter any work requiring the fuel circuit to be opened, pressurising the fuel circuit requires a procedure called "long pre-control" of the fuel pump. refer to chapter: pressurising the fuel supply circuit
Valve SCHRADER
The SCHRADER valve is like a tyre valve
Functions
- Depressurising the circuit
- Pressure check
- Delivery check
Fuel supply cut-off
Inertia switch
Application: according to version
The inertia switch "cuts" the fuel supply in the event of an impact
The inertia switch is reset by pushing the button in its upper section
Location: in the engine compartment
Multiplexed airbag ECU
Application: vehicles equipped with a multiplexed airbag ECU
If a pyrotechnic component is deployed, the fuel supply is cut off
Starting the vehicle
- Switch off the ignition
- Switch on the ignition (ignition switched +)
Booster pump (low pressure)
Role
Role of the booster pump: to supply the injection rail with fuel
A nonreturn valve, incorporated into the supply pump on the delivery circuit, maintains a residual pressure in the engine fuel system
Description
The fuel pump is submerged in the fuel tank
The fuel pump is supplied with 12 volts
The fuel pump is controlled on the order of the injection ECU by one of the following components
- The double injection relay
- The engine fusebox by an internal relay
Fuel filter
"A" assembly: description
Compiling
- Filter element (made of paper)
- Strainer
The strainer catches any paper scraps from the filtering element
Special features
- Filtration threshold: 8 to 10 micrometres
- Replacement interval: 60 000 kms
WarningRespect the fitting direction indicated by an arrow on the fuel filter's body
Location
The fuel filter is located to the fuel pump delivery pipe
"B" assembly
The fuel filter is incorporated in the tank unit/fuel pump module
Special features
- Filtration threshold: 8 to 10 micrometres
- Replacement interval: none, maintenance free
Fuel pressure regulator
Fuel pressure regulator incorporated into the sender unit
The petrol pressure in the injection rail is regulated by the petrol pressure regulator
Pressure in the petrol injector supply rail
- EW10 engine = 3,5 bars
- XU10 engine = 3,5 bars
- TU engine = 3 bars
"A" assembly
(1) fuel pressure regulator
"B" assembly
(17) fuel pressure regulator
Petrol injectors (1331, 1332, 1333, 1334)
Role
The injectors allow the quantity of fuel to be measured out
Function
Operation of the injectors at each electrical impulse
- The injector's needle is lifted from its seat
- The pressurised fuel is sprayed upstream of the valve seat
The injectors are operated separately in the firing order (1 - 3 - 4 - 2), just before the intake phase (sequential injection)
Electrical special features
Control: injection ECU
Data
- Supply voltage: 12V
- Resistance: ð 12 ohms