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Idle Speed: 2.3L

  1. Connect Super Star II scan tool to diagnostic connector. Enter KOER self-test. See TESTS W/CODES - EEC-IV (2.3L) article in the ENGINE PERFORMANCE section. After Code 11 or 111 has been displayed, unlatch and then, within 4 seconds, latch STI button. A single pulse code indicates that entry mode has been successfully entered.
  2. Observe scan tool readout. If a constant tone, solid light or STO LO is displayed, base idle speed is within range and no adjustment is necessary. Unlatch STI button to exit self-test.
  3. If a beeping tone, flashing light or STO LO at 8 Hz is displayed, Throttle Position (TP) sensor is out of range and should be checked. See THROTTLE POSITION (TP) SENSOR. Repeat KOER self-test.
  4. If a beeping tone, flashing light or STO LO at 4 Hz is displayed, base idle speed is too high. Go to step 6). If a beeping tone, flashing lighter STO LO at one Hz is displayed, base idle speed is too low. Go to next step.
  5. DO NOT clean throttle bore. Check throttle plate for presence of throttle plate orifice plug. See Fig 1 . If plug does not exist, turn idle adjusting screw clockwise only to adjust idle speed until conditions in step 2) are obtained. If plug from previous service exists, remove it and turn screw to obtain conditions in step 2). After adjustment is complete, ensure screw contacts lever pad.
    Fig 1: Locating Throttle Plate Orifices & Installing Plug (2.3L)
    G91E08159Courtesy of FORD MOTOR CO.
  6. Turn engine off. Using tape, block off orifice in throttle plate. See Fig 1 . If orifice is already plugged, go to step 9).
  7. On mass airflow engines, reconnect air cleaner hose. On all models, restart engine, and check idle speed. If engine stalls, crack throttle plate open using throttle plate stop screw. See Fig 2 . If idle speed is still too high as described in step 4), go to next step. If idle speed drops to specification or less as described in steps 2) and 4), go to step 9).
  8. Perform KOEO self-test. Refer to appropriate TESTS W/CODES - EEC-IV (2.3L) article in the ENGINE PERFORMANCE section. Check for fault codes, especially TP sensor fault code. If fault codes are present, repair as necessary. If TP sensor fault code is present, check for proper TP sensor output. See THROTTLE POSITION (TP) SENSOR. Ensure adjustment screw contacts lever pad. If no fault codes are present, see TESTS W/O CODES - EEC-IV (2.3L) article in the ENGINE PERFORMANCE section.
  9. Turn ignition off. Remove air cleaner hose, and remove tape covering throttle plate orifice. Select correct color plug for orifice. Plugs are available in Throttle Plate Plug Kit (FOPZ-9F652-A).
  10. Reconnect air cleaner hose, and start engine. Recheck idle speed. If idle speed is not within specification, turn adjusting screw clockwise until condition in step 2) is obtained. After adjustment, screw must contact lever pad.
  11. Perform KOEO self-test to ensure TP sensor fault code is not present. See TESTS W/CODES - EEC-IV (2.3L) article in the ENGINE PERFORMANCE section. Move throttle plate to ensure it is not stuck in bore and linkage is not keeping throttle from closing. On models with automatic overdrive transmissions, check throttle valve pressure adjustment.
NOTE: If electric cooling fan comes on, discontinue testing until fan goes off.
Fig 2: Locating Throttle Plate Stop Screw (Typical)
G91A08157Courtesy of FORD MOTOR CO.
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