Geely Emgrand X7. Manual part — 90

11. Dismantle the fixing bolts of the

mounting strap in the middle of
the fuel tank.

NL02-0402b

12. Dismantle the fixing bolts of the

mounting strap in the front of the
fuel tank.

13. Lower the fuel tank slowly.

NL02-0403b

14. Disconnect fuel pump harness

connector.

15. Carefully put the fuel tank down.

NL02-0404b

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Installation Procedure:

1

Lift fuel tank assembly.

2. Connect the fuel pump wiring

harness connector.

NL02-0405b

3. Install and tighten the fixing bolts

of the mounting strap in the front
of the fuel tank.

Torque :42 Nm(Metric)
31lb-ft(English system)

4. Install and tighten the fixing bolts

of the mounting strap in the
middle of the fuel tank.

Torque :42Nm(Metric) 31lb-ft(English
system)

5. Install and tighten the fixing bolts

of the mounting strap in the rear
of the fuel tank.

Torque :42Nm(Metric) 31lb-ft(English
system)

NL02-0403b

6. Connect the front fueling

ventilation hose and install the
fixing clamp.

7. Connect the left-front fuel tank

inlet pipe and the canister hose.

8. Fix the canister piping to the fuel

tank.

9. Connect the fuel tank inlet hose

and fasten the clamp.

10. Connect the fuel level sensor

harness connector.

11. Connect the battery negative

cable .

NL02-0399b

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2.4 Auxiliary Emission Control Device

2.4.1 Specifications

2.4.1.1 Fastener specifications

Torque Range

Fastener Name

Model

Metric (N.m)

English system
(lb-ft)

Fixing Bolts of Canister
Solenoid Valve Bracket

M6×12

8 - 9

5.9 - 6.7

Fixing Bolts of Canister
Assembly

M8×20

20 - 24

14.8 - 17.8

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2.4.2 Description and Operation

2.4.2.1 Heated Oxygen Sensor (HO2S)

Heated Type Oxygen Sensor (HO2S) are installed before and after the three-way catalytic
converter. Heated oxygen sensor sends signals to the engine control module (ECM) indicating
oxygen content in the exhaust. the engine control module controls the fuel injectors to change the
engine Air-fuel ratio. The ideal Air- Fuel ratio is 14.7:1, at this time the catalytic converters is the
most efficient. As the fuel injection system continuously measures and adjusts Air-Fuel ratio, it is
called "closed loop" control.

1. Open-loop

When the engine has just started and the speed is higher than 400 rpm, the system enter "open
loop" operation. In the open- loop mode, the engine control module (ECM) ignores the signal
from the heated type oxygen sensor (HO2S) signal according to signals from the temperature
sensor of engine coolant (ECT) and intake pressure temperature sensor to calculate the Air-Fuel
ratio. Sensors will remain in the "open loop" mode, until the following conditions are met:

z Heated type oxygen sensor voltage output changes, showing that the temperature is high

enough and the system can enter the normal operation.

z Temperature sensor of engine coolant is higher than the specified temperature.

z The engine has been started for the specified period of time.

2. Closed-loop

In the above mentioned situation, the specific values depend on different engines and are stored in
electrically erasable programmable read-only memory (EEPROM). When these conditions are met,
the system enters into "closed loop" operation. In the "closed loop", the engine control module
calculates Air-Fuel ratio according to oxygen sensor signals (ie, fuel injector connected timing), so
that the Air-Fuel ratio is always very close to 14.7:1.

Notes:

Once the engine control module confirms oxygen sensor faulty, the system will be immediately in
"open loop" control. The Air-fuel ratio is no longer adjusted according to the oxygen sensor
signals.

2.4.2.2 Evaporative Emission (EVAP) Control System

Evaporative emission control system uses the basic principle of Canister storage method. This
method transfers fuel vapor from fuel tank to the carbon storage devices in order to save the steam
when the vehicle is not running. When the engine is running, the fuel vapor is sucked out from the
Canister and burnt in the normal combustion process. Gasoline vapor from the fuel tank flows into
the fuel vapor recovery pipe. The vapor is absorbed by the Canister. After the engine runs the
required time, the engine control module provides a ground circuit, so that evaporative canister
clean-up solenoid valve is turned on and the air is drawn into the canister and mixed with vapor.
The mixture is then sucked into the intake manifold. The evaporative canister clean-up is
controlled by the pulse-width modulated solenoid valve (PWM) signal to open or close. According
to the operating conditions determined by air flow, fuel adjustment and intake air temperature,
evaporative Canister PWM duty cycle changes. The following conditions can cause poor idling,
stalling and poor performance:

z Canister Solenoid Valve Inoperation

z Canister Damage

z Hose Disconnected, Cracking, Improperly Connected To The Pipeline

Evaporative canister is an emission control device containing active carbon particles. Evaporative
Canister is used to store fuel vapor from fuel tank. When certain conditions are met, the engine
control module will provide the canister solenoid valve power, so that the fuel will be sucked into
the engine cylinder and burnt off.

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