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Spark Knock, Light To Moderate Acceleration

Article No.
00-12-3

Date:
6/12/00

SPARK KNOCK - LIGHT-TO-MODERATE ACCELERATION - 5.4L VEHICLES ONLY

FORD: 1998 EXPEDITION, F-150, F-250 LD
LINCOLN: 1998 NAVIGATOR

ISSUE

Some vehicles may experience spark knock during light-to-moderate accelerations. This may be caused by combustion chamber deposit buildups with time or distance increasing the fuel octane requirements, resulting in detonation.

ACTION

Proceed with normal diagnostics per the Powertrain Control/Emissions Diagnosis (PC/ED) Service Manual. If spark knock on acceleration cannot be eliminated through normal diagnostics, reprogram the Powertrain Control Module (PCM). Refer to the following Calibration Information Chart for details.





CALIBRATION INFORMATION

OTHER APPLICABLE ARTICLES: NONE

WARRANTY STATUS: Eligible Under The Bumper To Bumper Warranty Coverage

OPERATION DESCRIPTION TIME
001203A Preprogram Powertrain 0.4 Hr.
Control Module (PCM)

DEALER CODING
CONDITION
BASIC PART NO. CODE
12A650 42

OASIS CODES: 497000, 615500, 615600