Engine - Lack of Power
Article No.93-10-3
05/12/93
^ LACK OF POWER - 4.6L - ENGINE PERFORMING IN LIMITED OPERATING STRATEGY - VEHICLES BUILT BEFORE 2/16/93, 49 STATES, 3/3/93, CALIFORNIA
^ TRANSMISSION - 4R70W - LACK OF POWER - ENGINE PERFORMING IN LIMITED OPERATING STRATEGY - VEHICLES BUILT BEFORE 2/16/93, 49 STATES, 3/3/93, CALIFORNIA
LINCOLN-MERCURY:
1993 MARK VIII
CALIBRATION:
3-38L-R00 (49S), 3-38Q-R00 (California)
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:
There may be a lack of power when the engine is performing in a limited operating strategy (L.O.S.). The engine will operate in a half fuel, reduced spark condition. This is caused by the program in the powertrain control module.
ACTION:
Replace the powertrain control module with a revised powertrain control module. Refer to the 1993 Mark VIII EVTM, Page 151-7, for its location.
The L.O.S. condition will exist when the vehicle wiring harness is disconnected from the transmission for any reason, or if the PCM detects an OPEN in the electronic pressure control (EPC) circuit.
Additionally, if the Electronically Controlled Transmission Tester (Rotunda 007-00085) is used to diagnose any transmission concern, the PCM will consider this an OPEN circuit condition and enable L.O.S.
The correct strategy for EPC "OPEN" circuit detection should increase EPC pressure to a maximum level and maintain normal engine functions. A "SHORT" in the EPC circuit will enable the L.O.S. strategy.
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
WARRANTY STATUS:
Eligible Under Bumper To Bumper Warranty Coverage And Emission Warranty Coverage
OPERATION DESCRIPTION TIME
931003A Replace Powertrain Control 0.5 Hr.
Module
DEALER CODING
BASIC PART NO. CONDITION CODE
12A650 08
OASIS CODES:
504000, 614000, 614500, 614600