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Home >> Toyota >> 2002 >> 4Runner Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System Self-Diagnostics >> Diagnostic Tests >> DTC P1128: Throttle Control Motor Lock Malfunction >> Diagnosis & Repair
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Diagnosis & Repair

  1. Check resistance of throttle control motor. See THROTTLE BODY under IDLE CONTROL SYSTEMS in SYSTEM & COMPONENT TESTING - V6 & V8 article. If throttle control motor is okay, go to next step. If throttle control motor is defective, replace throttle body with throttle control motor as an assembly. See THROTTLE BODY under FUEL SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - V6 & V8 article.
  2. Remove air inlet hose from throttle body. Visually inspect throttle body for foreign material which may be caught between throttle valve and throttle body. If foreign material exists, remove foreign material and clean throttle body as necessary. If foreign material does not exist, replace throttle body. See THROTTLE BODY under FUEL SYSTEMS in REMOVAL, OVERHAUL & INSTALLATION - V6 & V8 article.