Chery A11 2003 Repair Manual page 295

Maintenance Manual for Chery·Windcloud
6). Instable idle speed occurs anytime
1 Set ignition switch in "ON". Check with scanner
to see if there is failure information record.
2 Check if idle speed actuator of idle speed stepper
motor is stuck (in case binding occurs in idle
speed stepper motor, this failure can not be read
from scanner, neither does it have failure code).
3 Switch on the ignition switch, and check if the
connections between water temperature sensor,
idle speed stepper motor and ECU are in good
condition.
4 Make engine run at idle speed, and stall cylinders
one by one to see if engine speed declines or
fluctuates.
5 Check the injector working condition of each
cylinder to see if it is in good order.
6 Check to see if the high voltage line resistance of
each cylinder is in good order.
7 Check if ignition coil is damaged.
8 Check if spark plug is in good order.
9 Connect fuel pressure gauge valve. Strap the 30#
and 87# pins of pump relay to make fuel pump
work, and then check if fuel pressure is at about
350kPa.
10 Provide 12V voltage directly from accumulator to
injector with special connector, and check if
injector is working in good order.
11 Recheck injector to see if it is working in good
order after cleaning.
12 Check if fuel is deteriorated or conatians water.
13 Check if fuel pressure is lower than 350kPa.
14 Shut down fuel gauge valve. Switch on ignition
switch again to make fuel pump work once more,
and check if fuel pressure is established.
15 Turn on fuel guage valve, clamp fuel return pipe
with fuel return interceptor to ensure no fuel
Marelli EFI System
Yes Eliminate
displayed
No Go to next step
Yes Repair or replace
idle speed actuator
No Go to next step
Yes Check wire harness
and
connector
No Go to next step
Yes Go to step 8
No Go to next step
Yes Go to next step
No Check injector and
wire harness
Yes Go to next step
No Replace
Yes Replace
No Go to next step
Yes Go to next step
No Replace spark plug
Yes Go to next step
No Go to step 13
Yes Go to step 12
No Go to next step
Yes Go to next step
No Replace injector
Yes Replace fuel
No Go to step 18
Yes Go to next step
No Go to step 17
Yes Go to next step
No Go to step 16
Yes Replace
pressure regulator
failure
socket
fuel
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