Back to 1998 Lexus SC 300

1998 LEXUS SC 300

3.0L I6RWDAUTOMATICgas
Repairs0Labor504Torque6016Fluid7DTC661Battery0Maintenance0Recalls0
P1652moderate severityPowertrain

Idle Air Control Valve Circuit

on 1998 Lexus SC 300 3.0L I6 · RWD

What this code means

The ECM detected a malfunction in the IAC valve control circuit.

Symptoms

  • CEL
  • High/low idle
  • Erratic idle
  • Stalling at idle
  • Surging

Common causes

  • Faulty IAC valve
  • Carbon in IAC passages
  • Damaged wiring
  • Poor ECM ground

Diagnostic steps

  1. Test IAC valve resistance
  2. Clean IAC passages
  3. Inspect wiring
  4. Check grounds

Repair notes

Clean or replace IAC valve.

Other Powertrain codes on this vehicle

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