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
NOTE:
- Before checking the idle speed, check these items:
-
- The malfunction indicator lamp (MIL) has not been reported on, and there are no DTCs.
- Spark plugs
- Air cleaner
- PCV system
- Apply the parking brake.
- HDS - Connect
- Idle Speed - Inspect
1. 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. 2. Check the idle speed under no load conditions: headlights, blower fan, radiator fan, audio system, and air conditioner off.
Idle speed should be:
6-Speed A/T:
680 ± 50 RPM (in P or N)
9-Speed A/T:
'16-18 680 ± 50 RPM (in P or N)
'19-21 710 ± 50 RPM (in P or N)3. 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:
6-Speed A/T:
680 ± 50 RPM (in P or N)
9-Speed A/T:
'16-18 680 ± 50 RPM (in P or N)
'19-21 710 ± 50 RPM (in P or N)NOTE: If the idle speed is not within specification, do the PCM Idle Learn Procedure . If the idle speed is still not within specification, go to the Fuel and Emissions Systems Symptom Troubleshooting Index .
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.
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.