Geely Emgrand X7. Manual part — 60

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If the vehicle does not have a misfire when sent to a service station, road test the vehicle, so
that the misfire will occur again. Use fault diagnosis tester to record ECM data when
misfire is occurring, in order to facilitate analyzing the cause of the fault.

–

If after a long period road test, ECM does not store any misfire associated DTC codes, then
the fault may be due to the following reasons:

•

Overfill fuel tank and fuel enters the evaporative emission control system, so that the
mixture is too thick and causes misfire.

•

Use improper fuel caused poor combustion and misfire.

•

Contaminated spark plug causes the ignition failure and misfire.

•

Carry out basic inspections at fault locations identified by DTC codes.

–

Road test the vehicle after repair to confirm no DTC is stored.

Step 1

Initial Inspection

(a) Inspect the harness connector for damage, poor connection, aging or signs of loosening.

(b) Inspect the vacuum tube for damaged, loose, leakage and so on.

Step 2

Inspect other DTC codes output.

(a) Connect fault diagnosis tester to the vehicle diagnostic interface.

(b) Turn ignition switch to ON position.

(c) Press the fault diagnosis tester power button.

(d) Select the following menu items: Engine/Read DTC codes.

(e) Read DTC codes.

Results

DTC Codes Shown

To Step

DTC codes other than P0300

No

DTCP0300 Yes

Step 3

Inspect the vacuum tube and the air intake system.

(a) Inspect vacuum canister solenoid valve connection is correct or not and leakage.

(b) Inspect the vacuum brake booster vacuum tube connection is correct or not and leakage.

(c) Inspect the intake tube pressure sensor connection is correct or not and leakage.

(d) Inspect the positive crankcase ventilation valve, ventilation pipe connection is correct or not

and leakage.

(e) Inspect whether there is any leakage in the intake system.

Is there any above mentioned fault?

No

Refer to 2.2.7.14 DTC Chapter Index.

Yes

Next

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Step 4

Inspect the spark plug

(a) Dismantle the spark plug from the misfire cylinder.

(b) Inspect whether the spark plug clearance is too large or too small.

Standard Gap: 1.0-1.1 mm (0.039-0.043 in)

(c Inspect the spark plug electrode for erosion and damage.

(d) Inspect whether the spark plug and the electrode part skirt is wet or not and Inspect the

existence of a serious gasoline leakage.

(e) Reinstall the spark plug.

The existence of the above faults?

Note: Prior to the implementation of this test, the following conditions must be met:

(a) Disconnect all fuel injector connectors.

B. Run the engine for no longer than 5s.

Step 5

Inspect whether the spark plug arcing is normal.

(a) Test

the

spark.

(b) Dismantle misfire cylinder ignition wires.

(c) Disconnect all fuel injector cylinder connectors.

(d) Install the spark plug to the ignition wires.

(e) Run the engine (the engine running time no longer than 5s) and inspect the arcing.

(f) Reconnect all cylinder fuel injector connectors.

(g) Install the ignition wires.

Is spark plug arcing normal?

Step 6

Inspect the misfire cylinder compression pressure.

The specific steps refer to 2.6.7.3 Cylinder Compression Test in 2.6Mechanical System.

Is cylinder compression pressure normal?

No

Go to step 9

Yes

Yes

Refer to 2.10.8.4 Replacement of Spark Plug to
replace the spark plug. Go to step 8

No

Yes

Repair the faulty part. Go to step 17

No

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Step 7

Refer to the 2.6.7 Diagnostic Information and Procedures in the Mechanical System to
inspect the cause for the low cylinder compression force.

Step 8

Inspect fuel and misfire cylinder fuel injectors.

(a) Inspect whether there is fuel injectors leakage and stagnate.

(b) Inspect

fuel

quality.

The existence of the above faults?

Note: Prior to the implementation of this test, the following conditions must be met:

(a) Disconnect all fuel injector connectors.

(b) Run the engine for no longer than 5s.

Step 9

Use a properly working spark plug and inspect whether there is misfire cylinder
jump-spark.

(a) Replace the installed spark plug with a spark plug that works properly.

(b) Test

spark

plug.

(c) Dismantle ignition guide wire of misfire cylinder .

(d) Disconnect all fuel injector cylinder connectors.

(e) Spark plug was installed on the ignition guide wire .

(f) Run the engine (the engine running time no longer than 5 s) and inspect the arcing.

(g) Reconnect all cylinder fuel injector connectors.

(h) Install

ignition guide wire .

Is spark plug arcing normal?

Step 10

Inspect ECM control connector terminal voltage of the misfire cylinder fuel injector.

Inspect the ignition coil and
ignition wire. Go to step 17.

No

Yes

Replace the spark plug. Refer to
2.10.8.4 Replacement of Spark
Plug Go to step 17

Yes

Repair the faulty part. Go to step 17

No

Yes

Go to step 10

No

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(a) Rotated ignition switch to ON

position .

(b) Connect ECM harness EM01.

(c) Measure ECM harness

connector EM01 terminal
voltage according to the
following table.

Connector terminal

Specified Value

EM01(6)

EM01(7)

EM01(8)

EM01(25)

9-14V

Is voltage the specified value?

Step 11

Inspect the misfire cylinder valve clearance.

Refer to the 2.6.8.21 Valve Clearance Adjustments in the Mechanical System, and is valve
clearance normal?

Step 12

Inspect valve timing system.

Refer to the 2.6.8.9 Replacement of Timing Chain Cover in the Mechanical System, and Is valve
timing normal?

No

Adjust the valve clearance. Go to step 17.

Yes

No

Inspect the fuel injector circuit. Refer to 2.2.7.29
DTC P0261、P0262.

Yes

ECM线束连接器

EM01

1

2

4

5

3

81

63

44

25

6

62

43

24 23 22 21 20 19 18 17 16 15 14 13 12 11 10

9

8

7

26

42 41 40 39 38 37 36 35 34 33 32 31 30 29 28 27

45

46

61 60 59 58 57 56 55 54 53 52 51 50 49 48 47

64

65

66

80 79 78 77 76 75 74 73 72 71 70 69 68 67

NL02-0033c

ECM harness connector EM01

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