Expedition 2WD V8-5.4L SOHC VIN L (1997)
PROM - Programmable Read Only Memory: All Technical Service Bulletins
PCM - MIL ON/DTC P0446 Set/Stall/Knock
Article No.
97-13-17
06/23/97
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MALFUNCTION INDICATOR LAMP (MIL)
ILLUMINATED - DIAGNOSTIC TROUBLE CODE
(DTC) P0446 STORED IN MEMORY - VEHICLES
BUILT THROUGH 3/97
^
MALFUNCTION INDICATOR LAMP (MIL)
ILLUMINATED - STALL ON DECELERATION
AND/OR SPARK KNOCK AT HOT AMBIENT
TEMPERATURES - VEHICLES BUILT THROUGH
3/97 WITH 4.6L ENGINE
^
LAMP - MALFUNCTION INDICATOR LAMP (MIL)
ILLUMINATED - DIAGNOSTIC TROUBLE CODE
(DTC) P0446 STORED IN MEMORY - VEHICLES
BUILT THROUGH 3/97
LIGHT TRUCK:
1997 EXPEDITION
CALIBRATION: 7-48J-R05, 7-48U-R05, 7-46F-R07, 7-46U-R07
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:
The Malfunction Indicator Lamp (MIL) may illuminate with Diagnostic Trouble Code (DTC) P0446 (Evaporative Emissions Control System Vent
Control Malfunction) stored in continuous memory on some 4.6L and 5.4L Expeditions. Some 4.6L Expeditions may experience a stall on deceleration
and/or spark knock at hot ambient temperatures. These concerns may be caused by the Powertrain Control Module (PCM) calibration.
ACTION:
Reprogram the PCM. Refer to the following Service Procedure for details.
SERVICE PROCEDURE
NOTE:
REGIONAL APPROVAL MUST BE OBTAINED WHEN IT IS NECESSARY TO REPLACE THE PCM. EMERGENCY ORDERS ONLY WILL
BE FILLED AS SHELF STOCK OF PCMs ARE LIMITED.
1.
Conduct normal diagnostics and repair as required.
2.
Check to verify vehicle does not have the latest calibration. If it does not, reprogram the PCM with the appropriate calibration, referring to the
PCM Application Chart above using the June, 1997 or later CD-ROM.
3.
After calibration update is complete, continue with normal diagnostics (visual inspection and road test) to determine root cause for DTC P1450
(formerly P0446) using Pinpoint Test HX56 on Page 5A-464 of the 1997 Powertrain Control/Emissions Diagnosis (PC/ED) Service Manual.
