SMU - SECTIONS 3A, 3B, 3D - REVISED INTAKE MANIFOLD. GMC Truck S15 Pickup - 2WD 1993

For 1990-2009 cars

# SMU - SECTIONS 3A, 3B, 3D - REVISED INTAKE MANIFOLD

#### SUBJECT: SERVICE MANUAL UPDATE - SECTIONS 3A, 3B, 3D - REVISED INTAKE MANIFOLD TUNING VALVE DIAGNOSIS

#### MODELS: 1993-95 CHEVROLET AND GMC TRUCK S/T AND M/L MODELS WITH 4.3L ENGINE (VIN W - RPO L35)

THIS BULLETIN IS BEING ISSUED TO INFORM THE TECHNICIAN OF THE FOLLOWING:

* THE INTAKE MANIFOLD TUNING VALVE DIAGNOSIS CHART FOR THE 1995 S/T TRUCK HAS BEEN REVISED.

* THE INTAKE MANIFOLD TUNING VALVE DIAGNOSIS CHART FOR THE 1993 AND 1994 S/T TRUCK AND THE 1993 THROUGH 1995 M/L VAN WAS OMITTED.

TECHNICIANS ARE INSTRUCTED TO UPDATE THEIR SERVICE MANUALS AS FOLLOWS:

* REPLACE THE CHART AND FACING PAGE LOCATED IN THE 1995 S/T TRUCK DRIVEABILITY, EMISSIONS AND ELECTRICAL DIAGNOSIS MANUAL FINAL EDITION ON PAGES 3A-62, 3A-63, 3B-40 AND 3B-41 WITH THE ATTACHED REVISED CHART AND FACING PAGE.

* INSERT THE ATTACHED CHART AND FACING PAGE INTO THE 1993 LIGHT DUTY TRUCK FUEL AND EMISSIONS SERVICE MANUAL BETWEEN 3D-44 AND 3D-45.

* INSERT THE ATTACHED CHART AND FACING PAGE INTO THE 1994 S/T TRUCK DRIVEABILITY AND EMISSIONS, AND ELECTRICAL DIAGNOSIS MANUAL.

* INSERT THE ATTACHED CHART AND FACING PAGE INTO THE 1994 M/L VAN DRIVEABILITY AND EMISSIONS, AND ELECTRICAL DIAGNOSIS MANUAL BETWEEN PAGES 3A-44 AND 3A-45.

* INSERT THE ATTACHED CHART AND FACING PAGE INTO THE 1995 M/L VAN DRIVEABILITY, EMISSIONS, AND ELECTRICAL DIAGNOSIS MANUAL BETWEEN PAGES 3A-36 AND 3A-37.

TECHNICIANS ARE INSTRUCTED TO USE THE REVISED CHART FOR DIAGNOSIS.

FIGURES: 00 ATTACHMENTS: 02

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.

COPYRIGHT 1996 GENERAL MOTORS CORPORATION. ALL RIGHTS RESERVED.