Chery QQ6 (S21) / S12LHD. Manual — part 202

wrapping material with care only when installing. The viser can be taken off only when the fuel

pump is to be installed. Takeoff of the filter net at fuel inlet is absolutely not allowed. The foreign

material that enters the fuel inlet of the fuel pump or the filter net may lead to damage of the fuel

pump.

8.5 Failure effects and judgment method
l Failure effect: strong running noise, poor acceleration, failure to start (starting difficulties) etc.
l Reasons for general failures: use of inferior fuel leads to:

1. Accumulated colloid became insulation layer;

2. Fuel pump bushing and armature blocked;

3. Components of fuel level sensor eroded.

l Maintenance precautions:

1. The electric fuel pump has different flow according to the requirement of engine. The pump

with same shape and possible to assemble perhaps is not available. For service, the part number of

replaced fuel pump must be in conformity with the original ones;

2. Do not run the pump at dry status to prevent the pump from accident;

3. Please pay attention to take cleaning measures for fuel tank and pipeline and replace fuel

filter in case replace fuel pump.

Simple measurement method:

1. With the joint removed, swift the digital multimeter on ohm shift, connect the two meter pens

to two pins of pump respectively to measure the inner resistance, it is indicated that is not at zero or

infinite (that is non short circuit, open circuit status).

2. With the joint connected, connect the fuel pressure gauge onto the sucker, start the engine

and then observe if the fuel pump works; if the fuel pump does not run, check if mains voltage is

present at “+” pin; if the fuel pump works, under idling mode, check if the fuel pressure is about

400kPa.

9. Injector

9.1 Function of injector:

ECU controls the coil of the injector through pulse to make the injector open or close, so that,

appropriate fuel will be injected into air intake pipe in due time to mix with air.

9.2 Working principle:

ECU sends electrical impulse to injector coil to form magnetic field force. When magnetic field

force increase to resultant force that enough to conquer return spring pressure, needle valve gravity

and friction force, the needle valve begin to rise up and start the injection process. The pressure of

return spring makes needle valve close again when the injection impulse is stopped.

9.3 Parameters of technical features

Value

Item

Min.

Typical

Max.

Unit

Operating pressure (pressure

difference)

350

KPa

Injector electric resistance at 20℃

11

16

W

Allowable fuel:

The injector can only use the fuel in compliance with the provisions in GB 17930-1999 (for

vehicle unleaded gasoline) and GWKB 1-1999 (harmful substance control standard for vehicle

gasoline), and detergent is required to be added into gasoline. It should be specially pointed out that

too long storage of gasoline may make it deteriorate. Especially, the taxi with a (LPG and gasoline)

dual-fuel engine uses LPG as fuel long and gasoline is only used for startup, so, daily consumption

of gasoline is little. However, because the fuel pump runs long, so the temperature of fuel tank is

quite high. If gasoline is stored in the fuel tank of such auto, it may quite liable to oxidation and

deterioration, which may lead to choke even damage of injector.

9.4 Installation attentions
l Use specific connector for certain injector and no mixed use will be allowable.
l For installation convenience, it is recommended to daub silica-free clean engine oil on the

1. O-ring

2. Filter net

3. Injector body with electric connector

4. Coil

5. Spring

6. Valve needle with coil armature

7. Valve seat with nozzle plate

Cross-section view of electromagnetic injector

Circuit diagram of electromagnetic injector

Connects to 87# pin of the
main relay

1# cylinder 1# cylinder 1# cylinder 1# cylinder

Injector

surface of the O-ring at the upside of the injector where it connects with the fuel distributing

pipe. Be careful not to let engine oil contaminate inside of the injector and the nozzle.

l Place the injector in its bracket vertically along injector bracket, then fix it to the bracket with

retaining clips. Note:

By location mode, the remaining clips for injector fall into axial location remaining clip and

①

axial and radial location remaining clip; misuse should be avoided.

For installation of an axially located in

②

jector, make sure that the bayonet at middle of the

remaining clip is completely locked into the groove of the injector and the grooves at both sides

of the remaining clip are completely locked into the outskirt flanging of the injector seat.

When instal

③

ling an injector that both axial and radial locations are required, use an axial and

radial location remaining clip and place the locating piece of the injector and the locating pin of

the injector seat respectively into the corresponding grooves on the location remaining clip.

If the injector has two grooves, be careful not to place by mistake, refer to the installation site

④

of the original.

l Installation of injector should be done by hand and knocking the injector with such tools as

hammer etc. is prohibited.

l When disassemble/reassemble the fuel injector, the O ring must be replaced. And pay attention

to not damage the sealing surface of the injector.

l Do not pull the support gasket of O-ring out of the injector. When installing, avoid damage to

fuel inlet end, support ring, nozzle plate and electric connector of the injector. If damaged, use

is prohibited.

l After installation of injector, perform leakproofness detection for fuel distributing pipe

assembly. It is acceptable only when no leakage exists.

l The failure part must be disassembled by hand. Remove remaining clip of the injector first, and

then pull out the injector from the injector seat. After disassembly, ensure cleanliness of the

injector seat and avoid contamination.

9.5 Failure effects and judgment method
l Failure effects: Poor idling, poor acceleration, failure to start (starting difficulties) etc.
l Reasons for general failures: failure caused by colloid accumulation inside the injector due to

lack of maintenance.

l Maintenance precautions: (see installation attentions)
l Simple measure method:

(remove the joint) swift the digital multimeter on ohm shift, connect the meter pens to the two pins

of injector. The rated resistance should be 11 - 16Ω¸ when it is 20

.

℃

Suggestion: regularly wash and analyze the injector using a special washer analyzer for injector.

10. Ignition Coil

10.1 Function of ignition coil:

Primary and secondary circuits are integrated inside the ignition coil; when ECU controls

on-off of current in the primary coil, a high voltage as high as thousands volts will be generated in

the secondary coil, which will then generate spark through ignition cable and spark plug to ignite the

mixed air in the cylinder.

10.2 Working principle

Ignition coil ZS - K2´2 consists of two primary windings, two secondary windings, mandrel, and

casing. When one of the primary windings grounding channel is connected, the primary winding is

in charging. Once the primary winding circuit is cut off by ECU, the charging will be stopped. At the

same time, the high voltage is sensed in the secondary winding and making the spark plug

discharging. There is a different with the distributor ignition coil: for the ignition coil ZS - K2´2,

there is one spark plug on both side of the secondary winding, so the both spark plugs can ignite at

the same time. These two primary windings power on/off alternatively, correspondently, these two

secondary windings discharge alternatively.

10.3 Technical characteristic

Value

Item

Min.

Typical

Max.

Unit

Nominal voltage

14

V

Primary winding

0.42

0.5

0.58

W

Resistance

(20 to 25

)

℃

Secondary

winding

11.2

13.0

14.8

kW

Primary winding

3.4

4.1

4.8

mH

Inductance

(20 to 25

)

℃

Secondary

winding

26.5

32.0

37.5

H

50pF load

30

kV

Voltage produced

50pF//1MW load

23

kV

10.4 Failure effects and judgment method
l Failure effects: start failure etc.
l Reasons for the failures: burn out due to too strong current, damage by external force etc.
l Maintenance precautions: use of “test ignition by short circuit” to test the ignition function is

prohibited during maintenance to avoid damage to the electronic controller.

l Simple measurement method:

With the joint removed, turn the digital multimeter to Ohm shift, and then connect the two meter

pens respectively to the two pins of primary winding. At 20

, the resistance should be 0.42

℃

-0.58Ω,

while this value of secondary winding should be 11.2-14.8kΩ.

Double spark ignition coil

87# pin of main relay