Engine - Rattle/Clatter Noise On Cold Driveaway
Article No.94-19-21
09/21/94
^ ENGINE - 5.8L - HIGH-PITCHED ENGINE "RATTLE/CLATTER" NOISE (SIMILAR TO EXHAUST SHIELD RATTLE) ON COLD DRIVEAWAY
^ NOISE - ENGINE "RATTLE/CLATTER" (SIMILAR TO EXHAUST SHIELD RATTLE) UNDER COLD DRIVEAWAY CONDITIONS
LIGHT TRUCK:
1993-94 F-150-350 SERIES
1994 BRONCO, ECONOLINE
This TSB article is being republished in its entirety to include updated calibration and part numbers.
CALIBRATION:
3-64G-R00, 3-64G-R10, 4-64E-R05, 4-64H-R00, 4-64K-R05, 4-64R-R00, 4-64S-R00, 4-75A-R00, 4-76A-R00, 4-76C-R00
WARNING:
THIS MODIFICATION IS AUTHORIZED ONLY FOR THE LISTED ENGINE. PERFORMING THIS MODIFICATION ON OTHER ENGINE CALIBRATIONS IS UNAUTHORIZED AND COULD CREATE LIABILITY UNDER APPLICABLE FEDERAL OR LOCAL LAWS.
ISSUE:
5.8L-equipped trucks may exhibit a high-pitched engine "rattle/clatter" noise, (similar to exhaust shield rattle) under cold driveaway conditions. This may be caused by the cylinder rate of pressure rise causing the top piston ring land to bounce against the cylinder bore.
ACTION:
Perform diagnosis, including a quick test, as outlined in Section 2A of the appropriate Powertrain Control/Emissions Diagnosis Service Manual (PC/ED). Service any Diagnostic Trouble Codes (DTC'S) as required. If the concern is still present, replace the Powertrain Control Module (PCM) with a revised service PCM as outlined in the PCM Replacement Chart shown in this article. The service PCM affects the cylinder rate of pressure rise during cold driveaway conditions.
NOTE:
VERIFY THAT INITIAL TIMING IS SET TO SPECIFICATION USING A ROTUNDA TIMING LIGHT OR THE SERVICE BAY DIAGNOSTIC SYSTEM (SBDS).
Refer to the following service publication reference(s) for service details:
^ Refer to the 1993/94 F-Series/Bronco Electrical And Vacuum Troubleshooting Manual (EVTM), Section 151, for component location views.
^ Refer to the 1994 Econoline Electrical And Vacuum Troubleshooting Manual (EVTM), Section 151, for component location views.
^ Refer to the 1993/94 Car/Light Truck PC/ED, Section 2A, for Diagnostic routines.
^ Refer to the 1994 Econoline, F-Series, Bronco, F-Super Duty Powertrain/Drivetrain Service Manual, Section 03-14, for component removal and installation procedures.
Obtain an Authorized Modifications Decal and list the date, dealer number, and summary of alterations performed. Select a prominent place adjacent to the Vehicle Emission Control Information Decal suitable for installing the Authorized Modifications Decal. Clean the area, install the decal, and cover it with a clear plastic decal shield.
Parts Block
OTHER APPLICABLE ARTICLES: NONE
SUPERSEDES: 94-15-20
WARRANTY STATUS: Eligible Under The Provisions Of Bumper To Bumper Warranty Coverage
OPERATION DESCRIPTION TIME
941921A Perform EEC-IV Quick Test, 1.0 Hr.
Check Engine Timing And
Adjust If Required,
Replace PCM - Econoline
941921B Perform EEC-IV Quick Test, 1.5 Hrs.
Check Engine Timing And
Adjust If Required, Replace
PCM - Bronco/F-Series/Lightning
DEALER CODING
BASIC PART NO. CONDITION CODE
RECAL 08
OASIS CODES: 497000, 499000, 702000, 702100