Grand Cherokee 2WD V8-5.2L VIN Y (1998)
PROM - Programmable Read Only Memory: Customer Interest
PCM - Cold Engine Sag/Hesitation
NO: 18-35-97
GROUP: Vehicle Performance
DATE: Dec. 31, 1997
SUBJECT:
Cold Engine Sag/Hesitation
MODELS:
1998 (AN) Dakota
1998 (BR/BE) Ram Truck
1998 (DN) Durango
1998 (ZJ) Grand Cherokee
NOTE:
THIS BULLETIN APPLIES TO VEHICLES WITH 5.2L ENGINES BUILT PRIOR TO NOV. 20, 1997 (MDH 1120XX).
SYMPTOM/CONDITION:
Sag or hesitation while accelerating from a stop with a cold engine or after a partial cool down.
DIAGNOSIS:
Using the Mopar Diagnostic System (MDS) or the Diagnostic Scan Tool (DRB III) with the appropriate Diagnostic Procedures Manual, verify all
engine/transmission systems are functioning as designed. If Diagnostic Trouble Codes (DTC's) are present, record them on the repair order and repair as
necessary before proceeding further with this bulletin. If no DTCs are present, perform the Repair Procedure.
NOTE:
WHENEVER A POWERTRAIN CONTROL MODULE (PCM) IS REPLACED DUE TO FAILURE, THE SOFTWARE OF THE
REPLACEMENT PCM SHOULD BE VERIFIED FOR THE LATEST REVISION LEVEL.
EQUIPMENT/PARTS REQUIRED:
1
CH6000
Scan Tool (DRB III)
1
CH7035
General Purpose Interface Bus Cable (GPIB)
1
CH7000/7001
J1962 Cable
1
04669020
Label - Authorized Software Update
1
04275086
Label - Authorized Modification
NOTE:
THE MDS AND DRB III ARE REQUIRED TO PERFORM PART OF THIS REPAIR AND THE SYSTEM MUST BE OPERATING WITH
RELEASE 21 OR HIGHER AND TIL CD RELEASE 1147 OR HIGHER MUST BE INSTALLED.
REPAIR PROCEDURE:
This bulletin involves selectively erasing and reprogramming the Powertrain Control Module (PCM) with new software (calibration changes).
1.
Connect the MDS (Mopar Diagnostic System) and DRB III (Scan Tool) to the vehicle and power them up.
2.
Use the arrow keys and select # 2 MDS DIAGNOSTICS on the DRB III MAIN MENU Screen.
3.
Use the arrow keys and select DIAGNOSTIC MENU on the MDS, then press NEXT MENU.
4.
Use the arrow keys and select VEHICLE CONTROLLER PROGRAMMING on the MDS, then press NEXT MENU.
5.
Use the arrow keys and select PROGRAMMING OF ALL OTHER CONTROLLERS USING MDS & DRB III on the MDS, then press NEXT
MENU.
6.
Follow the steps presented on the MDS and DRB III which will allow the DRB III to obtain the current part number of the PCM.
7.
The MDS will display the part number of the PCM on the vehicle and the appropriate replacement part number, then press NEXT MENU to begin
programming.
If the PCM on the vehicle has already been updated or programmed, a NO UPDATES AVAILABLE message will be displayed. Check the part number
of the PCM on the vehicle and compare it to the part number displayed. If the PCM has already been updated, then another condition exists that will
