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3.0L MPFI

  1. Turn off all lights and accessories. Place transmission in Neutral or Park. Ensure A/C-Heat selector is off. Apply parking brake and block wheels.
  2. Bring engine to normal operating temperature and check for vacuum leaks downstream of throttle plates. Disconnect spout line (single line connector), or remove shorting bar (double line connector), and ensure ignition timing is correct. Readjust if necessary.
  3. Shut off engine and disconnect air by-pass valve assembly connector. See Fig 1 . Remove PCV entry line at PCV valve. Install Orifice Tool (T86P-9600-A) in PCV entry line. Orifice diameter is 2" (5.0 mm).
    Fig 1: 3.0L MPFI Throttle Plate Stop Screw Adjustment (This Is Not A Normal Tune-Up Procedure)
    G10852
    NOTE: If electric cooling fan comes on during idle set, unplug fan motor or wait until fan shuts off before starting procedure.
  4. Start engine and let idle in Drive or Neutral. If idle speed is not within specification, adjust throttle plate screw. After idle has been set, shut off engine.
  5. Restart engine and check idle speed after 3 to 5 minutes. If not within specification, repeat step 4). After idle speed is within specification, shut off engine, remove orifice tool and reconnect PCV entry line. Reconnect spout line (single line connector), or replace shorting bar (double line connector).
  6. Reconnect ISC motor and cooling fan. Verify throttle plate is not stuck in bore and that throttle plate stop screw is setting on rest pad with throttle closed. Restart engine. After 3 to 5 minutes verify that engine RPM is within specification.
HOT (SLOW) IDLE RPM SPECIFICATIONS

Application Curb Idle RPM Throttle Stop RPM
3.0L MPFI
Auto. Trans. 875-925 820-870
Man. Trans. 990-1090 1015-1065