5.8L V8

The Idle Tracking Switch (ITS), located on carburetor, is a mechanically operated electric switch held open by throttle linkage when throttle is closed. It is used on the Extended Idle Air By-Pass system.

When ITS is opened, EEC module is signaled to deactivate the normally closed solenoid. When this happens, vacuum is removed from normally closed by-pass valve and thermactor air is released into atmosphere.