Suzuki Engine 2002 GRAND VITARA SQ625, Service Manual

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6E1-26 ENGINE AND EMISSION CONTROL SYSTEM (G16/J20 ENGINES)
Idle Speed/Idle Air Control (IAC) Duty Inspec-
tion
Before idle speed and IAC duty check, make sure of the following.
• Lead wires and hoses of engine/emission control systems
are connected securely.
• Accelerator cable has some play, that is, it is not tight.
• Valve lash is checked and adjusted according to mainte-
nance schedule.
• Ignition timing is within specification.
• All accessories (wipers, heater, lights, A/C, etc.) are out of
service.
• Air cleaner has been properly installed and is in good condi-
tion.
• ECM (PCM) does not detect any malfunction DTC.
After above items are all confirmed, check idle speed and IAC
duty as follows.
1) Connect SUZUKI scan tool to DLC (1) with ignition switch
OFF.
Special tool
(A) : SUZUKI scan tool
2) Warm up engine to normal operating temperature.
3) Check idle speed and IAC duty by using “Data List” mode of
SUZUKI scan tool.
If idle speed and/or IAC duty is out of specifications, check
idle air control system referring to “Diagnostic Flow Table B-4
Idle Air Control System Check” in Section 6-1.
Engine idle speed
A/C OFF : 750 ± 50 r/min.
A/C ON : 850 ± 50 r/min. for G16
800 ± 50 r/min. for J20
IAC duty at specified idle speed
2 – 30 %
4) Check that specified engine idle speed is obtained with A/C
ON if vehicle is equipped with A/C.
If not, check A/C signal circuit and idle air control system.
NOTE:
Before starting engine, place transmission gear shift
lever in “Neutral” (shift selector lever to “P” range for A/T
vehicle), and set parking brake and block drive wheels.
(A)
1