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Diagnosis & Repair

  1. Check air intake hose between throttle body and cylinder head. Check for loose, damaged or cracked hose. Repair as necessary. If air intake hose is okay, go to next step.
  2. Access ECM behind glove box. Turn ignition off. Disconnect ECM E7 connector. See Figure. Turn ignition on. Using DVOM, measure voltage between ground and terminals No. 22 (Yellow/Black wire) and No. 23 (Green/Black wire) at ECM E7 connector. If both readings are 9-14 volts, go to step 4). If any reading is not 9-14 volts, go to next step.
  3. Disconnect IAC valve connector. Measure resistance between Black/Orange wire terminal and Green/Black and Yellow/Black wire terminals at IAC valve. Resistance should be 17-25 ohms (cold) or 22-29 ohms (hot). If both readings are as specified, check for open or short circuit in wiring harness between junction block No. 2, located in left side of engine compartment, and ECM. See appropriate wiring diagram in WIRING DIAGRAMS article. If any reading is not as specified, replace IAC valve.
  4. Check IAC valve operation. See IDLE CONTROL SYSTEM in SYSTEM/COMPONENT TESTS article. Replace IAC valve as necessary. If IAC valve is okay, replace ECM and retest.
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