Idle Speed: Testing and Inspection

Idle Speed / Idle Air Control (IAC) Duty Inspection
Before idle speed / IAC duty check and adjustment, make sure of the following.
- Lead wires and hoses of engine and emission control Systems are connected securely.
- Accelerator cable has some play, that is, it is not tight.
- 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 condition.
- No abnormal air inhaling from air intake system.

Inspection of Idle Speed with A/C ON
Refer to "Idle Speed / Idle Air Control (IAC) Duty Inspection".

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 (1) with ignition switch OFF, if it is available.

Special tool
(A): SUZUKI scan tool

2. Warm up engine to normal operating temperature.
3. Check engine idle speed and IAC duty as follows:

Engine Idle Speed And IAC Duty:

a. Select "Data List" mode on scan tool to check IAC duty.
If duty and/or idle speed is out of specifications, inspect idle air control system.

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 circuits and idle air control system.