RUNS ROUGH/IDLE SHAKE/ HESITATES OR MISS. Chevrolet Beretta 1992

SUBJECT: RUNS ROUGH/IDLE SHAKE/HESITATES OR MISS

MODEL and YEAR: 1992-93 CAVALIER, CORSICA AND BERETTA WITH 2.2L (LN2) ENGINE

REVISION 08/17/93

THIS BULLETIN IS BEING REVISED TO ADD A SUPERSESSION STATEMENT. *********************************************************************

THIS BULLETIN CANCELS AND REPLACES CORPORATE BULLETIN 236108. THIS BULLETIN CANCELS AND SUPERSEDES DEALER SERVICE BULLETIN 92-226-6E, DATED JUNE 1992, A NEW PART NUMBER AND PROCEDURES HAVE BEEN ADDED. ALL COPIES OF 92-226-6E SHOULD BE DISCARDED.

CONDITION:

SOME OWNERS OF 1992-93 J OR L CARS MAY COMMENT OF ROUGH RUNNING AT IDLE, IDLE SHAKE, GENERALLY RUNS ROUGH, A MISS OR HESITATION.

CAUSE:

THE CAUSE OF THIS MAY BE AN INTAKE MANIFOLD GASKET OUT OF POSITION. THE GASKET IN SOME VEHICLES MAY WALK INWARD AND FOLD, CREATING AN INTAKE MANIFOLD LEAK.

CORRECTION:

INSTALL A NEW MOLY COATED INTAKE MANIFOLD GASKET USING THE PROCE- DURE BELOW: NEW INTAKE MANIFOLD GASKET P/N 24574409

NOTE: DO NOT USE THE OLD GASKET (P/N 10103647); USE ONLY THE NEW GASKET IDENTIFIED ABOVE.

PROCEDURE:

1. DISCONNECT NEGATIVE BATTERY CABLE. 2. RELIEVE FUEL PRESSURE ACCORDING TO SERVICE MANUAL SECTION 6E3-C2. 3. REMOVE AIR CLEANER DUCT ASSEMBLY AND TOP HALF OF THE AIR CLEANER. 4. DISCONNECT VACUUM LINES FROM THE FUEL PRESSURE REGULATOR, EGR, PCV AND POWER BRAKE BOOSTER. 5. POSITION TRANSAXLE FILL TUBE AND INDICATOR ASSEMBLY ASIDE; REFER TO SERVICE MANUAL SECTION 7A (AUTOMATIC TRANSAXLES ONLY). 6. REMOVE CABLE SPLASH SHIELD, CABLES AND CABLE BRACKET; REFER TO SERVICE MANUAL SECTION 6C. 7. DISCONNECT SECONDARY IGNITION WIRING FROM THE SPARK PLUGS AND UNROUTE HARNESS. 8. ROUTE POWER STEERING LINES UNDER THE AIR INLET BLOWER CASE. 9. LOOSEN THE POWER STEERING PENCIL BRACE BOLT AT THE POWER STEERING PUMP AND REMOVE THE POWER STEERING PENCIL BRACE BOLT AT THE INTAKE MANIFOLD. POSITION BRACE ASIDE (DO NOT REMOVE FROM VEHICLE). 10. ON L-CARS, POSITION THE MAIN ENGINE HARNESS RUNNING ALONG THE FRONT OF DASH TOWARD THE TOP OF THE FRONT OF DASH. ON J-CARS, POSITION THE GENERATOR HARNESS TO THE PULLEY SIDE OF THE POWER STEERING PUMP. 11. LOOSEN THE FUEL LINE RETAINER UNDER THE INTAKE MANIFOLD; REFER TO SERVICE MANUAL SECTION 6C. 12. REMOVE THE FUEL FEED HOSE RETAINER FROM THE INTAKE MANIFOLD; REFER TO SERVICE MANUAL SECTION 6C. 13. DISCONNECT BOTH FUEL LINES FROM THE INTAKE MANIFOLD; REFER TO SERVICE MANUAL SECTION 6C. 14. REMOVE THE INTAKE MANIFOLD FASTENERS. 15. REMOVE THE FOUR UPPER INTAKE MANIFOLD STUDS FROM THE CYLINDER HEAD. 16. REMOVE THE INTAKE MANIFOLD FROM THE CYLINDER HEAD. NOTE: A. MATING SURFACES MUST BE CLEAN AND FREE OF ANY FOREIGN MATERIAL, GREASE OR DIRT. B. DO NOT SAND OR ROUGH UP EITHER OF THE MATING SURFACES PRIOR TO INSTALLATION OF THE NEW GASKET. 17. CLEAN AND INSPECT THE INTAKE MANIFOLD AND CYLINDER HEAD MATING SURFACES. NOTE: C. INSTALL THE INTAKE MANIFOLD GASKET AGAINST THE CYLINDER HEAD BEFORE INSTALLING THE INTAKE MANIFOLD OR GASKET DAMAGE MAY RESULT. D. DO NOT USE ANY ADDITIONAL MATERIALS OR SEALANTS TO IMPROVE THE GASKET'S SEALING ABILITY. 18. INSTALL THE INTAKE GASKET AND MANIFOLD. 19. INSTALL AND TIGHTEN FOUR UPPER INTAKE MANIFOLD STUDS INTO THE CYLINDER HEAD. 20. TIGHTEN THE INTAKE MANIFOLD FASTENERS IN SEQUENCE TO THE SPECIFICATION SHOWN IN SERVICE MANUAL SECTION 6A2. 21. CONNECT BOTH FUEL LINES TO THE INTAKE MANIFOLD; REFER TO SERVICE MANUAL SECTION 6C. 22. INSTALL THE FUEL FEED HOSE RETAINER TO THE INTAKE MANIFOLD; REFER TO SERVICE MANUAL SECTION 6C. 23. ROUTE THE FUEL LINE UNDER THE FUEL LINE RETAINER AND TIGHTEN RETAINER; REFER TO SERVICE MANUAL SECTION 6C. 24. ROUTE THE WIRING HARNESS TO ITS ORIGINAL LOCATION; REFER TO SERVICE MANUAL SECTION 8A. 25. POSITION THE POWER STEERING PUMP PENCIL BRACE; INSTALL AND TIGHTEN THE POWER STEERING PUMP PENCIL BRACE TO INTAKE MANIFOLD BOLT. TIGHTEN THE POWER STEERING PUMP PENCIL BRACE TO PUMP BOLT. REFER TO SERVICE MANUAL SECTION 3B. 26. ROUTE POWER STEERING LINES TO THE CORRECT POSITION. 27. ROUTE AND CONNECT SECONDARY IGNITION WIRING. 28. INSTALL CABLE BRACKET, CABLES AND CABLE SPLASH SHIELD; REFER TO SERVICE MANUAL SECTION 6C. 29. POSITION TRANSAXLE FILL TUBE AND INDICATOR ASSEMBLY; REFER TO SERVICE MANUAL SECTION 7A (AUTOMATIC TRANSAXLES ONLY). 30. CONNECT VACUUM LINES TO THE FUEL PRESSURE REGULATOR, EGR, PCV AND POWER BRAKE BOOSTER. 31. INSTALL AIR CLEANER DUCT ASSEMBLY AND TOP HALF OF THE AIR CLEANER. 32. CONNECT NEGATIVE BATTERY CABLE.

PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.

WARRANTY INFORMATION:

LABOR OPERATION NUMBER: T3360 LABOR TIME: 1992 J OR L CARS: 1.7 HOURS AUTO TRANS, ADD: 0.1 HOUR

1993 J OR L CARS: 1.8 HOURS AUTO TRANS, ADD: 0.1 HOUR

FIGURES: 0

GENERAL MOTORS BULLETINS ARE INTENDED FOR USE BY PROFESSIONAL TECHNICIANS, NOT A "DO-IT-YOURSELFER". THEY ARE WRITTEN TO INFORM THOSE TECHNICIANS OF CONDITIONS THAT MAY OCCUR ON SOME VEHICLES, OR TO PROVIDE INFORMATION THAT COULD ASSIST IN THE PROPER SERVICE OF A VEHICLE. PROPERLY TRAINED TECHNICIANS HAVE THE EQUIPMENT, TOOLS, SAFETY INSTRUCTIONS AND KNOW-HOW TO DO A JOB PROPERLY AND SAFELY. IF A CONDITION IS DESCRIBED, DO NOT ASSUME THAT THE BULLETIN APPLIES TO YOUR VEHICLE, OR THAT YOUR VEHICLE WILL HAVE THAT CONDITION. SEE A GENERAL MOTORS DEALER SERVICING YOUR BRAND OF GENERAL MOTORS VEHICLE FOR INFORMATION ON WHETHER YOUR VEHICLE MAY BENEFIT FROM THE INFORMATION.