Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Idle Speed 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 timing
- Spark plugs
- Air cleaner
- PCV system
- Apply the parking brake, and make sure the headlights are off.
- Disconnect the evaporative emission (EVAP) canister purge valve connector.
- Connect the HDS to the data link connector (DLC) (A) located under the driver's side of the dashboard.
- Make sure the HDS communicates with the PCM. If it doesn't, go to the DLC circuit troubleshooting (see DLC CIRCUIT TROUBLESHOOTING ).
- Start the engine. Hold the engine speed at 3, 000 RPM without load (in P or N) until the radiator fan comes on, then let it idle.
- Check the idle speed under no load conditions: headlights, blower fan, radiator fan, audio system, and air conditioner off.
Idle speed should be:
740 ± 50 RPM (in P or N)
- Let the engine idle for 1 minute with high electric load (A/C on, temperature set to max cool, blower fan on high, headlights on high beam).
Idle speed should be:
740 ± 50 RPM (in P or N)
NOTE: If the idle speed is not within specification, do the PCM idle learn procedure (see PCM IDLE LEARN PROCEDURE ). If the idle speed is still not within specification, go to the applicable symptom troubleshooting . - Reconnect the EVAP canister purge valve connector.
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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