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Maximum Isc Extension - Eldorado & Seville Buick Roadmaster VIII

Adjustments ~216 words
  1. Before adjusting maximum Idle Speed Control (ISC) extension, check minimum idle and Throttle Position (TP) sensor adjustment. See MINIMUM IDLE under «IDLE SPEED»(ref-19418-S29919818412001010200000) . See «THROTTLE POSITION (TP) SENSOR»(ref-19418-S31535330762001010200000) .
  2. With ignition on and engine off, select ECM ISC MOTOR override ES03. See appropriate G - TESTS W/ CODES article in this section.
  3. Fully extend ISC motor by pressing WARMER button on Electronic Climate Control (ECC) panel. Fuel data center display should alternately change from 50 or 00 to 99, indicating override function has started.
  4. ISC should extend to maximum extend position. With ISC at maximum extended position, TP sensor parameter should indicate 13.0-13.8 degrees on Driver Information Center (DIC). If TP sensor is not 13.0-13.8 degrees, adjust ISC plunger clockwise or counterclockwise until TP sensor parameter indicates 13.4 degrees on DIC.
  5. Recheck maximum extend setting. Press COOLER button to retract ISC plunger. Wait 5 seconds. Press WARMER button, and check TP sensor angle (in degrees). Readjust ISC plunger if necessary.
  6. While still in diagnostic mode, turn ignition off. Allow about 20 seconds for ISC to retract and perform a TPS LEARN routine. Re-enter diagnostic mode, and turn ignition off. Successful TPS LEARN takes 2 cycles to occur. Start engine, and check for proper ISC motor operation. Clear codes.

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