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1991
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Syclone V6-262 4.3L Turbo
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Repair and Diagnosis
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Transmission and Drivetrain
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Automatic Transmission/Transaxle
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Testing and Inspection
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Symptom Related Diagnostic Procedures
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3L30 (180/180C) Automatic Transmission
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Downshift Right After Full Throttle Upshift & Closing Throttle
Downshift Right After Full Throttle Upshift & Closing Throttle
1. Detent valve stuck in open position.
2. Detent cable stuck.
3. Clogged or leaking vacuum modulator line.