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Tune-Up Notes

IDLE SPEED ADJUSTMENT CAUTION  - Procedures and specifications for idle speed adjustment must be followed exactly as outlined. See "Hot (Slow) Idle RPM" under Tune-Up  .

NOTE: For other items affecting Tune-Up, see CARBURETION  Section or EMISSION CONTROL  Section.
NOTE: Due to changes and corrections, always refer to Engine Tune-Up Decal in engine compartment before attempting tune-up. In the event of a conflict between specifications given in this manual and decal specifications, decal specifications prevail.
NOTE: For Tune-Up purposes only, Light Duty (L/D) will refer to all 1500 series, Suburban and Rally Van models. Heavy Duty (H/D) will refer to all remaining models.