A/T - AX4S Harsh 3-2 Downshifts During Braking
Article No.99-1-4
01/25/99
^ TRANSAXLE - AX4S - HARSH 3-2 DOWNSHIFTS
DURING BRAKING AND/OR COASTING TO A
STOP - VEHICLES EQUIPPED WITH 3.0L 2-VALVE
ENGINE
^ TRANSAXLE - AX4S - HIGHER ENGINE RPM THAN
EXPECTED AND HARSH BUMP ON 3-2 TORQUE
DEMAND DOWNSHIFT AT LIGHT THROTTLE
BETWEEN 16-24 KM/H (10-15 MPH) - VEHICLES
EQUIPPED WITH 3.0L 2-VALVE ENGINE
FORD:
1996 TAURUS
LINCOLN-MERCURY:
1996 SABLE
This TSB article is being republished in its entirety to revise the Issue.
CALIBRATION
6-10A-R07-R12, 6-10S-R07-R12
WARNING
THIS MODIFICATION IS AUTHORIZED ONLY FOR THE LISTED ENGINE(S). PERFORMING THIS MODIFICATION ON OTHER ENGINE CALIBRATIONS IS UNAUTHORIZED AND COULD CREATE LIABILITY UNDER APPLICABLE FEDERAL OR LOCAL LAWS.
ISSUE
Higher than expected engine rpm (slippage) and harsh bump on 3-2 torque demand downshift at light throttle (tip-in) between 16-24 km/h (10-15 mph), or a harsh 3-2 downshift while coasting to a stop and/or braking may be experienced on some vehicles. This may be caused by the Powertrain Control Module (PCM) calibration.
ACTION
Reprogram the PCM. Refer to the following Service Procedure for details.
SERVICE PROCEDURE
After recalibration of the PCM, it will be necessary for the PCM to relearn the correct idle speed control values before an acceptable 3-2 coastdown will be felt. Performing the following Steps will allow the PCM to relearn the correct idle speed control values.
1. Vehicle must be at operating temperature, Transmission Fluid Temperature (TFT) greater than 65°C (150°F) and Engine Coolant Temperature (ECT) greater than 82°C (180°F).
2. Set A/C to coolest temperature and fan speed to mid-range.
3. Turn off all lights and accessories.
4. Apply brakes to prevent the vehicle from moving.
5. Idle vehicle with shift lever in "D" position for 2 minutes with NC on and then 2 minutes with A/C off.
6. Drive the vehicle for 1.5 kilometers (1 mile), stop and repeat the idle in "OD" for 2 minutes with A/C on and 2 minutes with A/C off.
Obtain an Authorized Modifications Decal (FPS 8262 - obtainable through DOES II, 25/pkg) and list the date, dealer number, and summary of modifications 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.
OTHER APPLICABLE ARTICLES: NONE
SUPERSEDES: 97-15-12
WARRANTY STATUS: Eligible Under The Provisions Of Bumper To Bumper Warranty Coverage
OPERATION DESCRIPTION TIME
990104A Reprogram Powertrain 0.9 Hr.
Control Module (PCM) And
Relearn Idle
DEALER CODING
CONDITION
BASIC PART NO. CODE
RECAL 42
OASIS CODES: 502000, 503000, 504000