The "Minimum Idle Speed Adjustment" procedure in the 1988 Service Manual "Section 6E3-2C" has been revised. The revised procedure is as follows:
THROTTLE PLATE STOP SCREW (MINIMUM AIR RATE) ADJUSTMENT PROCEDURE
1. Remove throttle plate stop screw plate. 2. Back stop screw out until an air gap between the screw and the throttle lever can be seen by looking downward from above the throttle body. 3. Turn the stop screw in until it just contacts the throttle lever. 4. Turn the stop screw 1 1/2 turns further.
More throttle plate opening = lower IAC valve counts. Less throttle plate opening = higher IAC valve counts.
If necessary to change adjustment more than one half turn either way, other causes of incorrect idle speed should be investigated as previously mentioned.
5. Adjust TPS per Section "6E3-Cl".
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