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Fuel System Synchronization: 4.0L

NOTE: Fuel system synchronization is controlled by position of oil pump drive shaft assembly. Camshaft Position (CMP) sensor is located on top of oil pump drive shaft assembly on right side of engine.
  1. If CMP sensor and oil pump drive shaft assembly were removed from engine, go to next step. If only CMP sensor was removed from top of oil pump drive assembly without disturbing oil pump drive shaft assembly adjustment, no adjustment is necessary.
  2. Ensure a NEW oil pump drive shaft assembly-to-engine block gasket is installed onto engine. Temporarily install a pin punch or drift through access hole on side of oil pump drive housing. Align hole on pulse ring with hole in housing. See Fig 1 . If engine crankshaft or camshaft was not rotated, go to next step. If engine crankshaft or camshaft was rotated, CMP sensor relationship must be adjusted, go to step  4 .
    Fig 1: Aligning Pulse Ring
    G00011571Courtesy of DAIMLERCHRYSLER CORPORATION
  3. Install oil pump drive shaft assembly into engine while aligning oil pump slot. Rotate oil pump drive shaft assembly to its original position. Install hold-down bolt finger tight. Go to step  5 .
    CAUTION: DO NOT rotate engine against normal rotation to align timing marks.
  4. Remove ignition coil rail assembly. Remove cylinder No. 1 spark plug. Rotate engine (in direction of normal rotation) until pressure is felt in cylinder No. 1. Slowly continue to rotate engine until timing mark aligns with Top Dead Center (TDC) (zero degrees) on timing scale. Install oil pump drive shaft. If oil pump drive does not drop down flush with engine block, oil pump slot is not aligned properly. Remove oil pump drive shaft and rotate so oil pump slot aligns with shaft on bottom of oil pump drive shaft. Install oil pump drive shaft and rotate oil pump drive shaft assembly to its original position. Install hold-down bolt finger tight. Go to next step.
  5. Remove pin punch or drift from oil pump drive shaft assembly. Install CMP sensor onto oil pump drive shaft assembly. CMP sensor connector should be facing rear of engine (zero degrees). Connect CMP sensor connector. See Fig 2 . Install spark plug and ignition coil rail assembly (if removed). Go to next step.
    Fig 2: Locating Camshaft Position Sensor
    G00011572Courtesy of DAIMLERCHRYSLER CORPORATION
  6. Connect scan tool to Data Link Connector (DLC), located below driver's side of instrument panel, near steering column. Start engine. Ensure engine is at normal operating temperature. With engine idling, select SET SYNC from scan tool menu. Observe scan tool display.
  7. If scan tool displays IN RANGE and zero degrees, procedure is complete. If scan tool does not display IN RANGE and zero degrees, loosen hold-down clamp bolt and rotate oil pump drive shaft assembly until reading is as close to zero degrees as possible, and IN RANGE message is displayed. Tighten hold-down clamp bolt to 17 ft. lbs. (23 N.m). Turn engine off. Remove scan tool.
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