Technical Service Bulletins

Ford knock

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Ford knock

Some 2009-2010 Ford F-150 and F-Super Duty vehicles equipped with the 4.6L 3V or 5.4L 3V engine may exhibit a low frequency knocking noise from the engine at hot idle only. The noise is predominantly heard from the right front wheel well area and/or the RH engine cam cover. This noise may be generated from the RH variable camshaft timing (VCT) phaser assembly.

1. Check for possible DTCs. If no DTCs are present, proceed to Step 2. If DTCs are present, address these before proceeding.

2. Engine must be at full operating temperature, over 190 degrees F cylinder head temperature.

3. Connect IDS diagnostics tool and verify that the software version is at the latest level (63 or later required).

4. Begin a new vehicle session.

5. Open Tool Box selection.

6. Open Data Logger.

7. Select Powertrain Engine

8. Select PCM Data Logger.

9. Clear the pre-selected items by clicking the eraser icon button.

10. Select variable cam timing desired angle number (VCT_DSD).

11, Go to live display and press the tick mark.

12. Make sure that the PID (parameter identification) is highlighted with the dark lines above and below the data being displayed.

13. Press the number symbol (output state control mode) of the VCT_DSD number PID.

14. Press the Control Arm Activate (finger on the button) icon to enable manual control of the PID.

15. Use the plus button to command to 4 degrees (one click is equal to 1 degree). When commanding the advance, both banks will normally adjust.

16. Listen carefully to the low frequency knock noise while commanding the VCT_DSD from 0 to 4 degrees. Some higher frequency clatter is normal at or above the 5 degree advance. What is being pursued is for the level of the low frequency knock noise to be noticeably reduced when advanced from 4 to 5 degrees. If noise level is noticeably reduced as the VCT desired angle is commanded from 3 to 4 degrees, the noise source is the RH VCT phaser assembly. Proceed to Step 17. If the low frequency knock noise is not noticeably reduced at 4 degrees, refer to the workshop manual section 303-00 for engine noise diagnostics.

17. Due to normal engine dynamics, the VCT phaser knock noise is produced by the RH VCT phaser assembly. Replace only the RH VCT phaser assembly, P/N 3R2Z-6A257-DA.

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