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Home >> Eagle >> 1990 >> Summit Base, Automatic >> Repair and Diagnosis >> Engine Performance >> Engine Controls - Adjustments >> Idle Speed & Mixture >> Basic Idle Speed >> Test No. 1
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Test No. 1

  1. Loosen throttle cable. Turn ignition on for more than 15 seconds. DO NOT  start engine. Turn ignition off. This should fully retract ISC motor plunger.
  2. Disconnect harness connector(s) from Idle Speed Control (ISC) motor. Ensure ISC plunger is in fully retracted position. Unscrew fixed speed adjusting screw (SAS) until throttle valve is fully closed. See Figure -Figure .
    CAUTION: When cleaning throttle body, plug air by-pass hole in throttle body to prevent solvent from entering passage.
  3. Start engine. If basic idle speed is within specification, go to step 6). If basic idle speed is not within specification, remove air intake hose and clean throttle body. Reconnect air intake hose. Check basic idle speed.
  4. If basic idle speed is not within specification after cleaning throttle body, adjust basic idle speed by turning idle speed adjusting screw. See Figure -Figure . After adjusting basic idle speed, turn fixed SAS screw clockwise until engine speed begins to increase.
  5. Turn fixed SAS screw counterclockwise until engine speed decreases. Turn fixed SAS screw counterclockwise an additional 1/2 turn from point at which engine speed no longer decreases. Turn off engine.
  6. Adjust throttle cable. Reconnect harness connector(s) at ISC motor. Start engine. Operate engine for approximately 5 minutes. Ensure engine idles within curb idle speed specification.
  7. Turn ignition off. Disconnect negative battery cable for at least 10 seconds to clear diagnostic trouble code. Reconnect negative battery cable. Operate engine at idle for approximately 5 minutes to ensure engine idles smoothly.
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