Chery QQ6 Service Manual download pdf (Page 17)

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.

1 2 ... 12 13 14 15 16 17 18 19 20 21 22 ... 84 85

No comments

Chery QQ6 Service Manual Page 17