Idle Speed: Testing and Inspection

ENGINE IDLE SPEED
MEASUREMENT
1. Before checking idle speed check the following:
a. Ensure that air cleaner element is free from clogging, ignition timing is correct, spark plugs are in good condition, and that hoses are connected properly.
b. Ensure that malfunction indicator Light ("CHECK ENGINE" light) does not illuminate.

2. Warm-up the Engine.





3. Connect Subaru Select Monitor or the OBD-II General Scan Tool to Data Link Connector.

CAUTION: When connecting Subaru Select Monitor, turn ignition switch to "OFF".

4. Start the engine and measure engine speed.

NOTE: Engine speed is indicated on Subaru Select Monitor by selecting "MODE FO4".





NOTE:
- When using the OBD-II General Scan Tool, carefully read its operation manual.
- When Subaru Select Monitor is not used, attach the pickup sensor on tachometer (secondary pickup type) to #1 cylinder spark plug cord.
- This Ignition System provides simultaneous Ignition for #1 and #2 plugs. It must be noted that some tachometers may register twice that of actual engine speed.

5. Check idle speed when unloaded. (with headlights, heater fan, rear defroster, radiator fan, air conditioning, etc. "OFF")

Idle speed (No load and gears in neutral, manual transmission (m/t) or N or P, automatic transmission (A/T) position): 700 ± 100 rpm.

6. Check idle speed when loaded. (Turn Air Conditioning (A/C) switch to "ON" and operate compressor for at least one minute before measurement.)

Idle Speed A/C "ON", no load and gears in neutral (M/T) or N or P (A/T) position): 850 ± 50 rpm.

CAUTION: Never rotate idle adjusting screw. If idle speed is out of specifications, refer to General On-board Diagnosis Table, please refer to Powertrain Management; Computer and Control Systems.