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Jet Valve Adjustment

  1. Before adjusting, note the following:
    • Misadjusted jet valve clearance will adversely affect emission levels.
    • Adjust jet valve clearance before adjusting intake valve clearance.
    • Before adjusting jet valve, retighten cylinder head bolts (cold) to 51-64 ft. lbs. (69-86 N.m) on 1.4L and 1.6L engines or 65-72 ft. lbs. (87-97 N.m) on 2.0L and 2.6L engines.
    • Adjust jet valve clearance with intake valve adjusting screw fully loosened.
  2. With engine at normal operating temperature, stop engine, remove rocker cover and position appropriate piston at TDC of compression stroke.
  3. Back off intake valve side adjusting screw 2 or more turns. Loosen lock nut on jet valve adjusting screw.
  4. Back off jet valve adjusting screw (counterclockwise) and place 0.006" (.15 mm) feeler gauge between top end of jet valve stem and bottom end of adjusting screw. See Fig. 2. 
  5. Turn down adjusting screw (clockwise) until proper clearance is obtained.
    NOTE: Tensile strength of jet valve spring is weak. DO NOT force screw to turn, putting excess pressure on spring.
  6. Hold adjusting screw and tighten lock nut. Recheck clearance. Adjust intake valve clearance to 0.006" (.15 mm). Repeat adjustment at each cylinder.
    Fig 1: Cutaway View of Chrysler Corp. Jet Air System
    G09315591Courtesy of CHRYSLER GROUP, LLC
    Fig 2: Adjusting Jet Valve Clearance
    G09315592Courtesy of CHRYSLER GROUP, LLC