Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

Cannot Adjust Idle Speed To Specification

1. When the idle speed is out of specification and the Malfunction Indicator Lamp (MIL) does not blink Diagnostic Trouble Code (DTC) 14, check the following items:
- Adjust the idle speed.
- Air conditioning signal
- Alternator FR signal
- A/T gear position signal
- Starter Switch signal
- Brake switch signal
- Power Steering Pressure switch signal [Except Canada]
- Fast idle thermo valve
- Hoses and connections
- Idle Air Control (IAC) Valve and its mounting 0-rings

2. If the above items are normal, substitute a known-good IAC Valve and readjust the idle speed.

3. If the idle speed still cannot be adjusted to specification (and the MIL does not blink code 14) after IAC Valve replacement, substitute a known-good Engine Control Module (ECM) and recheck. If symptom goes away, replace the original ECM.

NOTE: On Canadian models the MALFUNCTION INDICATOR WARNING LAMP is the CHECK ENGINE LAMP.