A/C SYSTEM MOAN NOISE (REPLACE A/C HOSE ASSEMBLY). Pontiac Trans Sport 1997

SUBJECT: A/C SYSTEM MOAN NOISE (REPLACE A/C HOSE ASSEMBLY)

MODELS: 1997-98 CHEVROLET VENTURE 1997-98 OLDSMOBILE SILHOUETTE 1997-98 PONTIAC TRANS SPORT

CONDITION:

SOME CUSTOMERS MAY COMMENT ON A MOAN TYPE NOISE THAT BECOMES EVIDENT WHEN THE A/C COMPRESSOR CLUTCH IS ENGAGED. THIS CONDITION IS MOST NOTICEABLE WHEN ENGINE IS AROUND THE 1000-2000 RPM RANGE. THE NOISE MAY BE LOUDEST WHEN THE ENGINE IS UNDER LIGHT ACCELERATION THROUGH THIS RPM RANGE.

CAUSE:

THE MOAN NOISE MAY BE CREATED BY COMPRESSOR PULSES WHICH SET UP A SYSTEM RESONANCE BETWEEN THE COMPRESSOR AND THE IN-LINE MUFFLER.

CORRECTION:

THIS CONDITION MAY BE CORRECTED BY REPLACING THE A/C COMPRESSOR TO CONDENSER HOSE ASSEMBLY. THE NEW HOSE ASSEMBLIES HAVE REPOSITIONED MUFFLERS DESIGNED TO CORRECT THE MOAN NOISE. REFER TO SECTION #1 IN THE SERVICE MANUAL FOR HOSE ASSEMBLY REPLACEMENT PROCEDURE.

PARTS INFORMATION:

P/N DESCRIPTION ============= ===============================================

10419475 HOSE, ASM - A/C COMPRESSOR + CONDENSER (C34)

10419476 HOSE, ASM - A/C COMPRESSOR + CONDENSER (C60)

PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.

WARRANTY INFORMATION:

FOR VEHICLES REPAIRED UNDER WARRANTY, USE:

LABOR OPERATION LABOR OPERATION NUMBER DESCRIPTION TIME =============== ==================================== ===============

D3088 HOSES AND/OR LINES, REFRIGERANT - USE PUBLISHED REPLACE LABOR OPERATION TIME

FIGURES: 00 ATTACHMENTS: 00

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.