KE15 - Engine RPM Error During Self-Test

Diagnostic Trouble Code (DTC) 411 indicates that during Engine Running Self-Test, engine rpm could not be controlled within the Self-Test lower limit band.

Possible causes:

- Improper idle air flow set.

- Vacuum leaks.

- Throttle linkage binding.

- Throttle plates open.

- Improper ignition timing.

- Idle Air Control (IAC) solenoid contamination.

- IAC circuit short to ground.

- Damaged IAC solenoid.

- Does engine Idle speed appear normal?

Yes -- Remove IAC solenoid and Inspect for contamination. If contamination is present, determine if solenoid is a type that can be cleaned.

Hitachi Idle Air Control (IAC) Valve And Solenoid:

Hitachi
This type of IAC solenoid is serviceable and may be removed and cleaned of sludge deposits that accumulate within the valve.

Hitachi Idle Air Control (IAC) Valve And Solenoid:

Hitachi With Vent/Filter
This type of IAC solenoid is not serviceable and cannot be cleaned.

No contamination present or solenoid cannot be cleaned: Replace IAC solenoid. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)

Solenoid is contaminated and can be cleaned: Clean as necessary. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)

If Diagnostic Trouble Code (DTC)/symptom is still present, replace IAC solenoid.

No -- Reset idle airflow to specification. Refer to Fuel Delivery and Air Induction for idle airflow adjust procedure. If unable to reset idle to specification, go to KE16. KE16 - Check For Condition Affecting Idle