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Extended Idle Air By-Pass System

  1. With engine at normal operating temperature and transmission in "N", begin timing. If after 2 1/2 minutes Thermactor By-Pass Valve releases secondary air through vents, system is operating properly. If not, check routing and condition of hoses, and of By-Pass Valve.
  2. If valve is operating correctly, check battery voltage to ITS. Also check for continuity through normally closed ITS while manually cycling switch. If correct, check that solenoid is functional and actually opens to close off vacuum. If solenoid is okay, turn engine off. Turn ignition switch to "ON" position. After 2 1/2 minutes, check vacuum signal to solenoid.