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Compression Test 2.3L

  1. Make sure the oil in the crankcase is of the correct viscosity and at the correct level and that the battery is correctly charged. Operate the vehicle until the engine is at normal operating temperature. Turn the ignition switch to the OFF position, then remove all the spark plugs. REFER to: Spark Plugs - 2.3L EcoBoost (231kW/314PS)/2.3L EcoBoost (257kW/350PS) - MI4
    GFD599725Courtesy of FORD MOTOR COMPANY
  2. Loosen the Throttle Body (TB) inlet pipe clamp and then position the Throttle Body (TB) inlet pipe aside.
    GFD599726Courtesy of FORD MOTOR COMPANY
  3. NOTE: When disconnecting the Throttle Body (TB) electrical connector disengage the red locking tab on the Throttle Body (TB) electrical connector by sliding it to the rear of the Throttle Body (TB) electrical connector, away from the Throttle Body (TB). Squeeze the Throttle Body (TB) electrical connector while removing.

    Disconnect the Throttle Body (TB) electrical connector.

    GFD599727Courtesy of FORD MOTOR COMPANY
  4. Set the throttle plates in the wide-open position.
  5. Install a compression gauge in the No. 1 cylinder.
  6. Install an auxiliary starter switch in the starting circuit. With the ignition switch in the OFF position, and using the auxiliary starter switch, crank the engine a minimum of 5 compression strokes and record the highest reading. Note the approximate number of compression strokes necessary to obtain the highest reading.
  7. Repeat the test on each cylinder, cranking the engine approximately the same number of compression strokes.
    GFD599726Courtesy of FORD MOTOR COMPANY
  8. NOTE: When connecting the Throttle Body (TB) electrical connector engage the red connector locking tab after fully installing the Throttle Body (TB) electrical connector. The red tab will not slide forward unless the Throttle Body (TB) electrical connector is fully installed.

    Connect the Throttle Body (TB) electrical connector.

    GFD599728Courtesy of FORD MOTOR COMPANY
  9. Install the Throttle Body (TB) inlet pipe and then tighten the Throttle Body (TB) inlet pipe clamp. Torque: 48 lb.in (5.4 Nm).
  10. Install the spark plugs. REFER to: Spark Plugs - 2.3L EcoBoost (231kW/314PS)/2.3L EcoBoost (257kW/350PS) - MI4