Idle Speed: Testing and Inspection

IDLE SPEED/IDLE AIR CONTROL (IAC) DUTY INSPECTION
Before idle speed/IAC duty check, make sure of the following.
- Lead wires and hoses of Electronic Fuel Injection and 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 maintenance 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 condition.
- No abnormal air inhalling from air intake system.
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, if it is available.
2. Warm up engine to normal operating temperature.




3. Check engine idle speed and "IAC duty" as follows:

When using SUZUKI scan tool:
1. Select "Data List" mode on scan tool to check "IAC duty" and engine speed.

When using duty meter:
1. Disconnect scan tool from DLC if connected.
2. Set tachometer.
3. Using service wire, ground "Diag switch terminal" in monitor connector and connect duty meter between "Duty output terminal" and "Ground terminal" of monitor connector.




If duty and/or idle speed is out of specifications, inspect idle air control system referring to Diagnostic Flow Table B-4 IDLE AIR CONTROL SYSTEM CHECK.

NOTE:
- Above duty values are ON duty meter indications.
- Duty values with (*) are applicable to vehicle used at high altitude (higher than 2,000 m or 6,560 ft).

4. Remove service wire from monitor connector.
5. Check that specified engine idle speed is obtained with A/C ON if vehicle is equipped with A/C.
If not, check A/C ON signal circuit and idle air control system.