Idle Speed: Testing and Inspection
CURB IDLE SPEED CHECKRequired Special Tool:
- MB991502: Scan Tool (MUT-II)
1. Before inspection's set vehicles to the following conditions:
- Engine coolant temperature: 80 - 95°C (176 - 203°F)
- Lights and all accessories: OFF
- Transaxle: Neutral (P range on vehicles with A/T)
CAUTION: To prevent damage to scan tool MB991502, always turn the ignition switch to the "LOCK" (OFF) position before connecting or disconnecting scan tool MB991502.
2. Connect scan tool MB991502 to the data link connector.
3. Confirm basic ignition timing is within the standard value.
Standard value: 5° BTDC ± 3°
4. Start the engine.
5. Run the engine at idle for 2 minutes.
6. Check the idle speed. Select MFI service data item number 22 and take a reading of the idle speed.
Curb idle speed: 700 ± 100 r/min
NOTE: The idle speed is controlled automatically by the idle air control system.
7. If the idle speed is outside the standard value, refer to Diagnosis - Symptom Chart.