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Home >> Buick >> 1994 >> Roadmaster Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 7 (Engine Controls - System/Component Tests) >> Ignition System >> Timing Control Systems >> Ignition Control (IC) Timing Advance System
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Ignition Control (IC) Timing Advance System

WARNING: This page is about a different car, the 1994 Cadillac Fleetwood. However, it is still accessible from the selected car via links, so may be relevant.
  1. A malfunction in the IC circuit (formerly referred to as the EST circuit) should set a related diagnostic trouble code. Start engine and warm to operating temperature. On vehicles equipped with a manual transmission, increase engine speed to about 2000 RPM. On vehicle equipped with an automatic transmission, slightly increase idle speed.
  2. Ground DLC "test" terminal "B" (not applicable to all models). A noticeable change in engine speed should occur. If no change occurs, see DIAGNOSTIC CIRCUIT CHECK in BASIC TESTING article in this section.