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.
Circuit Description
IAC system controls idle speed by allowing a controlled amount of air to by-pass throttle blade via a passage in IAC valve. ECM controls IAC system to maintain a desired idle speed. Speed may vary depending on input to ECM and other criteria. If ECM detects engine speed is outside IAC system's range of control at idle, this DTC will set.
Conditions required to set DTC are:
- Actual engine RPM is greater than desired idle speed by at least 200 RPM.
- Short term air trim is lower than -1.66 gm/s.
- Fuel cutoff occurs greater than 3 times when diagnostic is performed.
- Conditions are met for greater than 8 seconds.
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra 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.