Chery S11 / Chery QQ. Manual — part 227

Chery QQ Maintenance Manual 465 EFI System

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Oxygen sensor

The diagram of oxygen sensor

Oxygen sensor connects with cable. The
other end of cable is electric connector.
There is asbestos
Cover on outside.
Pins on connector:
No.1: Connect heat source (+)/white
No.2: Connect heat source (-)/white
No.3: Connect signal (-)/gray
No.4: Connect signal (+)/black

Feature curve of oxygen sensor at 600 C

6、ECU
Usage: ECU is central part of electronic
control system. Sensors supply every signal
for ECU. After calculation, ECU will
control the action of actuator such as
injector and ignition coil to control engine
operation.
Constitute: There are shield shell and PC
board in ECU. Many electronic control units
are interated on the board to control EFI
system.
Install: ECU is fixed under instrument panel
by screws. Note to insert pins vertically
during installation, otherwise it will cause
terminals getting out to influence the normal
operation of engine.

Output

Chery QQ Maintenance Manual 465 EFI System

Out view and internal construction of ECU

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Chery QQ Maintenance Manual 465 EFI System

Pins on ECU

Power: The battery supplies voltage to ECU through pin 18. When main relay is on, battery
supplies voltage through pin 37 and when ignition switch is on, battery supplies voltage
through pin 27.
Attention: Pin 8 and pin 52 are used for making richer fuel/air mix during after-sale service.
They are mainly used on bad engine starting condition because of aging parts or bad part.

pin

Method 1

Method 2

Method 3

Method 4

Not used

Ground

Not used

Ground

Not used

Not used

Ground

Ground

degree

Normal

Thick

Thicker

Thickest

Control method for pin 8 and pin 52

7. Fuel pump
Usage: Fuel pump feeds fuel with certain pressure and quantity to engine.
Constitute and principle: The pump consists of DC motor, vane motor and cover (together
with stop return valve, leak valve and anti-electromagnetic interference elements). The pump
and motor are mounted on same shaft and sealed in same shell. Pump and motor in shell are
surrounded by fuel for radiation and lubrication.
Battery supplies voltage to pump through pump relay. The relay only switches on pump
circuit during engine starting and running. When engine stops for malfunction, pump will stop
automatically. The maximum pressure on outlet of pump is decided by leak valve that is
between 450kPa and 650 kPa. But the pressure in whole fuel system fluctuates with the
fluctuating of intake manifold pressure. Fuel regulator decides the differential (usually is
300kPa ) between system pressure and manifold pressure.
Note: The temperature of fuel has great influence on pump function. When working under
high temperature for a long time, the pump pressure will drop rapidly if fuel temperature is
over certain value. If engine cannot be heat started, please check carefully whether the high
temperature working function is good.

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Chery QQ Maintenance Manual 465 EFI System

Fuel pump

The diagram of fuel pump

Pins: There are 2 pins on pump to connect pump relay. Marks “+”and“-”are cut on the shell
of pump.

8. Injector
Usage: Injector injects atomized fuel to engine in specified time according to instruction of
ECU.
Constitute and principle: ECU sends pulses to injector coil to form magnetic field force.
When the force increased enough to overcome the resultant force of spring pressure, weight of
needle valve and friction, needle valve begins to lift and inject process starts. The maximum
lift height of needle valve does not exceed 0.1mm. When inject pulses stop, needle valve
closes again by the pressure of return spring.
Install hint: The injector must use suitable connector.
In order to mounting easily, recommend to smear non-silicon clear oil on the surface of
O-ring connected with fuel distribution pipe. Pay attention to not pollute internal injector and
injector hole by oil.
Install injector to the seat vertically to injector seat, then clamp injector on the seat by clip.
Note: For long stopped vehicle, please check carefully if the fuel cohered blocks injector.
Diagnosis: S11 EFI system does not diagnose the injector itself, but diagnoses for injector

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