Chery A11. Manual — part 116

direction, loosen fuel pipe.

* Hold seat collar firmly, pull fuel pipe off as arrow direction.

(5) Fuel rail

Fuel rail is used for distributing fuel into fuel injector and fixing fuel injector.

(6) Fuel injector

This system uses top fuel supply single hole fuel injector. Fuel injection pressure is 3.5bar，

output fuel is continuously atomized and in cone angle (15°angle from fuel injector axes )。

The control logic of fuel injector is: phase, sequence control. Four fuel injectors is controlled

according to four cylinders air intake sequence, opening in power stroke till intake stroke start.

Fuel injectors are fixed on fuel rail. Fuel rail press injector onto the fixed seat of intake

manifold, and is sealed by 2 O-rings.

1.upper O-ring 2.lower O-ring 3. fuel inlet 4.coil 5.wire terminal 6.electrical

connector

Fig4 Fuel Injector Diagram

2. Air system

Air intake system mainly consists of air filter, intake hose, intake manifold, idle step

motor and throttle valve body of throttle position sensor.

(1) Throttle valve body

Throttle valve body calculate air intake volume upon throttle pedal depressing status. Auxiliary

air intake volume is regulated by step motor when engine idles.

To avoid condensation and freezing under some conditions, throttle valve regulator bar

is against anti-stuck screw preventing throttle from full closed. . The anti-stuck screw is

adjusted during throttle valve body calibrating by manufacturer and do not turn the screw.

Fig 5 Outside Drawing of Throttle valve

1. throttle cable coil 2. Anti-stuck Screw 3.step motor 4.throttle position sensor

(2) Idle step motor

Idle step motor is used for controlling

idle speed ,directly fixed on throttle valve

body consists of one step motor and

screw/worm retard unit which change the

rotational movement of locking pin to linear

movement. After receiving control

command of ECU, step motor axially

moves valve spindle (about 0.04mm/step)

using screw/worm unit , by which change

by-pass air charge volume when engine

idles to control idle speed.

When temperature is at 20 ℃ , coil

resistance is R=53±10Ω. The maximum

air charge is achieved through backing 200

steps of locking valve. The amounts of

working step is determined upon engine operating conditions including warming up, A/C on

etc.

Fig 6 Idle Control Valve Operation Theory

1.Step motor 2. control valve 3.by-pass hole

4.throttle valve

3. Control system

(1) ECU

ECU is located in the cabin of engine, connected to wiring harness via 80-pin interface.

ECU is used for handling signals from various sensors and controlling actuators to obtain

optimum operating conditions..

Comparing to the previous mode, it has added many functions. But due to using of

many customized circuits of special functions, it has powerful integration, compact structure,

and small size.

ECU handle following signals:

- battery voltage;

-intake manifold absolute pressure ；

-Top Dead Center；

-throttle position；

-air intake temperature；

-Engine coolant temperature；

-A/C operation；

-oxygen sensor signal；

-knocking sensor signal。

Air charge efficiency is calculated upon managed intake manifold absolute pressure,

intake air temperature, engine speed and throttle position, by which air charge volume in

cylinder is obtained.

ECU controlsas below:

- Control fuel injection by controlling open time of fuel injector；

-Idle step motor；

-Four high voltage output ignition coil；

-carbon canister solenoid；

-A/C compressor；

- Warning indicator

Besides those functions, ECU can also controls：

-all self-diagnostics strategies on input sensors

and output actuators；

-“Wrong” signal recovery strategy on basic valid input signal；

Fig 7. Throttle valve position

sensor

A. Voltage positive B. ground C.

-Engine anti-theft function

(2) Throttle position sensor

Throttle position sensor is used for measuring throttle opening, determining idle, full

load and accelerating/decelerating operating conditions, and carry out fuel injection volume

control corresponding with throttle opening. Throttle position sensor includes a

potentiometer, and the moving parts is operated by throttle shaft. During operation, ECU

supply 5V voltage to sensor and measured parameter is variable of throttle opening from

minimum to maximum.

Operation Operational theory of throttle position sensor is shown as fig 7.

(3) TMAP sensor (air intake temperature, pressure sensor)

★ TMAP sensor combined air intake temperature sensor and air intake pressure
sensor .

Air intake pressure sensor is an important sensor, which utilize pressure-resistance effect
of semi-conductor element, transferring pressure change in intake manifold to voltage
change.

Air intake temperature sensor is used to measure air intake temperature, which is a
negative temperature coefficient (NTC) resistance thermo-sensitive element.And the
resistance decrease with temperature increasing.

(4) Crankshaft speed and position sensor

This system adopts electromagnetic crankshaft speed and position sensor with inner
composition of watered magnet round cylinder and coil. Crankshaft speed and position
sensor are fixed on transmission housing, corresponding with sensor signal gear tooth.
Sensor signal gear has 60-2 teeth. When 1-4 cylinder is in Top Dead Center position，the
sensor is at the 20

th

tooth counting from signal gear absent tooth; and when 2-3 cylinder is

in Top Dead Center position，the sensor is at the 50

th

tooth counting from signal gear absent

tooth.

Fig 7. Crankshaft speed and position sensor Operation Theory

1. Crankshaft speed and position sensor 2. Signal gear 3. Corresponding signal with 2nd absent tooth 4. Signal

Besides identification of Top Dead Center position，signal can be used by ECU for:

-Managing of ignition (ignition advance angle and charging duration)；

-generating rotaional speed signal；

-Confirming synchronization of each engine revolution by identifying the two absent
teeth.

Under the condition of other factors not changing, the peak value of sensor output
voltage is determined on the distance between crankshaft rational speed and position
sensor and gear tooth. The clearance between the head of crankshaft rotational speed and
position sensor and the top of signal gear tooth is 1±0.5mm.

(6) Oxygen sensor