Chery QQ6 Service Manual download pdf (Page 53)

12. Steps for Implementation of Failure Diagnosis by Engine

Symptom

12.1 Perform Preliminary Inspection First before Following the Steps for

Implementation of Failure Diagnosis by Engine Symptom.

(1) Make sure that ECU and failure indicator lamp (or EPC lamp) have no off-normal

phenomenon (excluding the models that have no failure indicator lamp).

(2) Use a failure diagnostic tester to check and make sure no failure information record

exists.

(3) Employ failure diagnostic tester to check that hot idle data from electronic control

system fall within normal scope.

Hot idle speed parameter table:

Name Parameter

Air intake temperature 20-70℃

Battery voltage 12-14V (affected by engine revolution)

Temperature of engine coolant 80-90 (normal operating temperature)℃

Position of accelerator pedal 0%~99.00%

Air-fuel ratio control integrator 5%-5%

Ignition advance angle

5-10° (may change with fluctuation of

engine revolution)

Outer corner of throttle 0%~99.61%

Fuel injection time 2-7ms (has a strong relation with engine

revolution)

Engine revolution n Expected idle speed ± 50rpm

Duty cycle of canister control valve 0%~99.9%

Self-adapting value of air-fuel ratio

control

0.95-1.05

Self-adapting value of air-fuel ratio

control

120-140

Intake manifold absolute pressure 350-650hPa

Voltage of oxygen sensor Quickly fluctuates at 0.1-0.9V

Air intake pressure

(4) Validate that the failure effect the owner complained exists and then locate the exact

position of the symptom. Please note that the information provided by the customer is

very important, especially the failure symptoms, occurrence time, position and if any

other failure symptoms occurred before; these information can help technical personnel

rapidly and effectively judge the failure, thus increasing maintenance speed and

improving maintenance quality.

Then check the appearance:

1 2 ... 48 49 50 51 52 53 54 55 56 57 58 ... 84 85

No comments

Chery QQ6 Service Manual Page 53