Engine - Cold Rough Idle/Driveline Clunk

NUMBER: 18-005-02

GROUP: Vehicle Performance

DATE: February 11, 2002

THIS BULLETIN IS BEING PROVIDED IN ADVANCE. THE MDS2 MUST BE OPERATING WITH CIS CD2102 OR HIGHER, AVAILABLE MARCH 4, 2002.

SUBJECT:
Vehicle Performance Enhancements

OVERVIEW:

This bulletin involves selectively erasing and reprogramming the JTEC Powertrain Control Module (PCM) with new software (01Cal19).

MODELS:

2001 TJ Wrangler

NOTE:
THIS BULLETIN APPLIES TO 2001 (TJ) JEEP WRANGLERS EQUIPPED WITH A 4.0L ENGINE AND CALIBRATION LEVEL PRIOR TO (LESS OR LOWER THAN) THOSE LISTED IN THE OVERVIEW ABOVE.

SYMPTOM/CONDITION:

Some vehicles may exhibit one or both of the following conditions:

1. Rough idle after a cold start up.

2. "Tip out" driveline clunk immediately following a closed throttle (manual transmission equipped only.)





PARTS REQUIRED:





EQUIPMENT REQUIRED:

REPAIR PROCEDURE:

1. Log onto the MDS2 (Mopar Diagnostic System).
2. Connect the MDS2 and DRB III(R) to the vehicle and switch the ignition key to "ON".

NOTE:
AUTO CONNECTION WILL OCCUR ONCE THE DRB III(R) MDS2, AND VEHICLE ESTABLISH COMMUNICATION. THE "CANNOT READ VIN FROM DRB III(R) MESSAGE (ON THE MDS2) WILL BE REPLACED BY THE VEHICLE VIN. PRESS THE "OK" BUTTON ON THE MDS2 TO REQUEST A MDS2 SESSION FOR THE VEHICLE VIN INDICATED. PRESS THE "OK" BUTTON WHEN ASKED TO BEGIN SESSION.

3. Push the FLASH tab on the MDS2.

4. Select READ PART NUMBERS FROM VEHICLE and click SHOW UPDATES on the MDS2.

NOTE:
A MESSAGE MAY APPEAR (AFTER STEP 3 OR 4) THAT INDICATES NO UPDATES ARE AVAILABLE. IF THIS OCCURS, MAKE SURE YOUR DIAGNOSTIC EQUIPMENT IS OPERATING AT THE LATEST SOFTWARE LEVEL AS LISTED EARLIER IN THIS BULLETIN. IF THE LATEST SOFTWARE IS INSTALLED, AND NO UPDATES ARE AVAILABLE ANOTHER VEHICLE CONDITION EXISTS THAT WILL REQUIRE FURTHER INVESTIGATION.

5. Select the new software part number with the light pen and click UPDATE CONTROLLER SOFTWARE.

6. The MDS2 and DRB III(R) will prompt for any operator action needed during the remainder of the reprogramming process.

NOTE:
DUE TO THE PCM REPROGRAMMING PROCEDURE, A DTC MAY BE SET IN OTHER MODULES (EATX, BCM, MIC, SKIM, ETC.) WITHIN THE VEHICLE, IF SO EQUIPPED. SOME DTC'S MAY CAUSE THE MIL TO ILLUMINATE. ALL DTC'S RELATE TO A LOSS OF COMMUNICATIONS WITH THE MODULE THAT IS BEING REPROGRAMMED. CHECK ALL MODULES, RECORD THE FAULTS, AND ERASE THESE FAULTS PRIOR TO RETURNING THE VEHICLE TO THE CUSTOMER. ERASE ANY FAULTS IN THE PCM ONLY AFTER ALL OTHER MODULES HAVE HAD THEIR FAULTS ERASED.

NOTE:
THE FOLLOWING STEPS ARE REQUIRED BY LAW.





7. Type the necessary information on the "Authorized Software Update Label" p/n 04669020 (Fig. 1). Attach the label to the PCM and cover the label with the clear plastic overlay.





8. Type the necessary information on the "Authorized Modification Label" p/n 04275086 and attach the label near the VECI label. (Fig. 2)

POLICY:
Reimbursable within the provisions of the warranty.





TIME ALLOWANCE:





FAILURE CODE: