Operation CHARM: Car repair manuals for everyone.

ECM - Rough Idle/Sag on Initial Launch

NO.: 18-21-92
GROUP: Driveability
DATE: Dec. 14, 1992

SUBJECT:
Rough Idle/Startup Dieout And/Or Sag/Hesitation Following
Cold Engine Startup - 3.0L MMC Automatic Transaxle

THIS BULLETIN SUPERSEDES TECHNICAL SERVICE BULLETIN 18-06-91 WHICH SHOULD BE REMOVED FROM YOUR FILES. THE SBEC (POWERTRAIN CONTROL MODULES) HAVE BEEN REVISED.

MODELS:

1990 (AA) Acclaim/Spirit/LeBaron Sedan
(AC) Dynasty/New Yorker Salon
(AG) Daytona
(AJ) LeBaron Coupe/LeBaron Convertible
(AQ) Chrysler's TC (Maserati Coupe)
(AS) Caravan/Grand Caravan/Caravan C/V
Voyager/Grand Voyager/Town & Country

SYMPTOM/CONDITION:

Some vehicles may experience rough idle, sag soon after initial launch or startup dieout following a cold start. This may occur when the engine is cold and the ambient temperature is between 60~F and 90~F.

DIAGNOSIS:

Using MDS or the DRB II (Scan Tool) and appropriate diagnostic procedure manual, verify that all vehicle engine systems are functioning as designed. If messages/fault codes (diagnostic trouble codes) are present, record them on the repair order for future reference, and repair as necessary. If no messages/fault codes (diagnostic trouble codes) are present and all systems are functioning correctly, proceed with the following repair.

PARTS REQUIRED:

1 Single Board Engine Controller (SBEC - Powertrain Control Module) for 3.0L MMC
with Automatic Transaxle:

AA, AG, AJ Federal 4740810

AA, AG, AJ California 4740811

AC Federal 4740814

AC California 4740815

AQ Federal 4740812

AQ California 4740813

AS Federal 4740816

AS California 4740817

1 Authorized Modification Label 4275086

REPAIR PROCEDURE:

This repair involves replacement of the Single Board Engine Controller (SBEC - Powertrain Control Module) with a revised one.

1. With the ignition key in the OFF position, disconnect the battery.

2. Remove the SBEC (Powertrain Control Module) as outlined in the appropriate service manual, and replace the SBEC (Powertrain Control Module) with unit called out in PARTS REQUIRED.

3. Connect the battery.





4. Type the required information on the Authorized Modification Label, as illustrated, and attach near the VECI Label.

POLICY:
Reimbursable within the provisions of the warranty.

TIME ALLOWANCE:
Labor Operation No. 08-19-91-99 0.4 Hrs.

FAILURE CODE: AM - Authorized Modification