Idle Speed/Idle Air Control Duty; Inspection - Suzuki 2000 Grand Vitara SQ625 Service Manual

ENGINE AND EMISSION CONTROL SYSTEM (G16 / J20 ENGINES) 6E1-19
IDLE SPEED/IDLE AIR CONTROL (IAC) DUTY

INSPECTION

Before idle speed and IAC duty check, make sure of the following.
D Lead wires and hoses of engine/emission control systems are
connected securely.
D Accelerator cable has some play, that is, it is not tight.
D Valve lash is checked and adjusted according to maintenance
schedule.
D Ignition timing is within specification.
D All accessories (wipers, heater, lights, A/C, etc.) are out of ser-
vice.
D Air cleaner has been properly installed and is in good condition.
D ECM (PCM) does not detect any malfunction DTC.
After above items are all confirmed, check idle speed and IAC duty
as follows.
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.
1) Connect SUZUKI scan tool to DLC with ignition switch OFF.
Special Tool
(A): SUZUKI scan tool, Tech 1
(B): Mass storage cartridge
(C): 16/14 pin DLC cable (OBD-II adapter cable)
2) Warm up engine to normal operating temperature.
1. DLC
3) Check idle speed and IAC duty by using "Data List" mode of SU-
ZUKI scan tool.
Engine idle speed
IAC duty at specified idle speed
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 "ENGINE DIAGNOSIS" section.
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.
A / C OFF A / C ON
850 + 50 r / min.
750 + 50 r / min.
for G16
800 + 50 r / min.
2 – 30 %
for J20