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Maximum Isc Extension (Eldorado & Seville) Chevrolet Corvette C4

Adjustments ~169 words
  1. Before adjusting maximum Idle Speed Control (ISC) extension, check minimum idle and Throttle Position Sensor (TPS) adjustment. See MINIMUM IDLE under V8 IDLE SPEED. Also, see THROTTLE POSITION SENSOR (TPS).
  2. With ignition on and engine off, select ECM ISC MOTOR override ES03. See ENTERING SELF-DIAGNOSTICS in appropriate G - TESTS W/ CODES article in this section.
  3. Fully extend ISC motor by pressing WARMER button on the Electronic Control Center (ECC) on dash. 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, TPS parameter should read 13.0-13.8 degrees on Driver Information Center (DIC). If TPS is NOT 13.0-13.8 degrees, adjust ISC plunger. Adjust ISC plunger, clockwise or counterclockwise, until TPS parameter reads 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 TPS voltage. Readjust ISC plunger if necessary.

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