Idle Speed Adjustment

IDLE SPEED/ISC DUTY ADJUSTMENT (INCLUDING A/C VSV ADJUSTMENT)

Before idle speed check and adjustment, 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.

After above items are all confirmed, check idle speed and ISC duty as follows.


NOTE: Before starting engine, place transmission gear shift lever in "Neutral", and set parking brake and block drive wheels.


1. Warm up engine to normal operating temperature.

Grounding Diagnosis Switch Terminal:

2. Ground diagnosis switch terminal in monitor connector and make sure that "CHECK ENGINE" light indicates diagnostic code No. 12. If code 12 does not flash, refer to Powertrain Management/Computers and Control Systems/Testing and Inspection/Procedures.

Connecting Duty Meter:

3. Stop engine and connect duty meter between duty check terminal and ground terminal of monitor connector.

The monitor connector is located near battery.

4. Connect tachometer.
5. Turn ON ignition switch and wait for 5 seconds. Then restart engine and run it at 2,000 rpm for 5 minutes to warm it up completely and let it slow down to idle speed.

Idle Speed Adjusting Screw:

6. Check ISC duty and idle speed. If duty and/or idle speed is out of specifications, adjust it by turning idle speed adjusting screw.

BASE ENGINE IDLE SPEED
800 ± 50 rpm
ISC DUTY AT SPECIFIED BASE IDLE SPEED
50%

7. Upon completion of adjustment, install adjusting screw cap to throttle body.
8. Remove service wire from monitor connector.
9. Check idle speed in closed loop.

CLOSED LOOP IDLE SPEED
Manual Transmission
A/C OFF 800 ± 50 rpm
A/C ON 1000 ± 50 rpm
Automatic Transmission
In Park or Neutral
A/C OFF 800 ± 50 rpm
A/C ON 1000 ± 50 rpm
Other Than Park or Neutral
A/C OFF 800 ± 50 rpm
A/C ON 800 ± 50 rpm

10. If not within specification, check A/C on circuit and ISC circuit.