Idle Speed & Mixture Adjustments
Idle speed is maintained by the Powertrain Control Module (PCM). No adjustment is necessary or possible.Inspection
Before checking the idle speed, check these items:
The malfunction indicator lamp (MIL) has not been reported on, and there are no DTCs.Ignition timingSpark plugsAir cleanerPCV system
- Apply the parking brake.
- Disconnect the Evaporative (EVAP) emission canister purge valve connector.
Connect the HDS to the Data Link Connector (DLC) located under the driver's side of the dashboard.
- Start the engine. Hold the engine speed at 3,000 rpm without load (in Park or neutral) until the radiator fan comes on, then let it idle.
- Check the idle speed without load conditions: headlights, blower fan, radiator fan, and air conditioner off. The idle speed should be 680-780 rpm (in Park or Neutral).
Let the engine idle for 1 minute with high electric load (A/C switch ON, temperature set to Max Cool, blower fan on High, and headlights on high beam). The idle speed should be 680-780 rpm (in Park or Neutral).
NOTEThe idle learn procedure must be done so the PCM can learn the engine idle characteristics. Do the idle learn procedure whenever you do any of these actions:
If the idle speed is not within specification, do the PCM idle learn procedure, as follows:
- Make sure all electrical items (A/C, audio, lights, etc.) are off.
- Reset the PCM with the HDS.
- Turn the ignition switch ON (II), and wait 2 seconds.
- Start the engine. Hold the engine speed at 3,000 rpm without load (in Park or neutral) until the radiator fan comes on, or until the engine coolant temperature reaches 194 ºF (90 ºC).
Let the engine idle for about 5 minutes with the throttle fully closed.
NOTEIf the radiator fan comes on, do not include its running time in the 5 minutes.
- Reconnect the EVAP canister purge valve connector.