GM Service Manual Online
For 1990-2009 cars only

CHUGGLE, TIP-IN HESITATION EGR AND PROM INSTALLATION

A NEWLY CALIBRATED PROM, #1226031 AND EGR VALVE #17079013 ARE BEING RELEASED FOR THE CORRECTION OF ANY ONE OF OR COMBINATION OF THE CONDITIONS LISTED BELOW ON 1982 CALIFORNIA "G" CARS (INCLUDING "G" WAGONS) WITH 3.8L V6 ENGINES, WHEN IT HAS BEEN DETERMINED THAT AFFECTED SYSTEMS ARE WITHIN SPECIFICATIONS AND FUNCTIONING NORMALLY. A.CHUGGLE AT 40-45 MPH B.TIP-IN HESITATION BEFORE A DECISION IS MADE TO INSTALL BOTH PARTS, VEHICLE SHOULD BE ROADTESTED FOR THE OWNER DESCRIBED CONDITIONS. UNLESS ALL OTHER AREAS ARE CORRECT, THE PROM AND EGR VALVE WILL NOT BE EFFECTIVE FOR THE PURPOSE INTENDED. USE THE ATTACHED CHECKLISTS FOR ADDITIONAL ASSISTANCE IF NECESSARY. A.CONDITION: CHUGGLE ALSO REFERRED TO AS SURGE, IS MOST NOTICEABLE AT 40-45 MPH AND SHOULD NOT BE CONFUSED WITH "FREEWAY HOP", A COMMON CONDITION IN MANY AREAS. CONVERTER CLUTCH ENGAGE SPEED IS INCREASED TO 50 MPH FROM 41 MPH. B.CONDITION: TIP-IN HESITATION MAY BE EXPERIENCED DURING EITHER HOT OR COLD OPERATION WHILE GOING THROUGH A LIGHT OR MODERATE ACCELERATION PERIOD FROM A STATIONARY VEHICLE POSITION. IF ANY ONE OR COMBINATION OF CONDITIONS EXIST, INSTALL BOTH PARTS, PROM AND EGR VALVE. PARTS INFORMATION OBTAIN THE FOLLOWING TWO (2) PARTS FROM YOUR NORMAL GM PARTS DIVISION WAREHOUSE: A.PROM #1226031 EGR VALVE #17079013 ORIGINAL EQUIPMENT PROM# 16030034 PROM ID "BOH" GM PARTS DIVISION WILL NOTIFY DEALERS THROUGH A SALES INFORMATION BULLETIN WHEN PARTS ARE AVAILABLE. CHUGGLE CHECK LIST 1.PARK-NEUTRAL BACK UP LIGHT SWITCH ADJUSTMENT 2.BASE IGNITION TIMING AND TOTAL ADVANCE 3.SPARK PLUGS AND PLUG WIRES 4.HEI OPERATION AT PROBLEM SPEEDS - INCLUDES CHECKING FOR CORRECT DISTRIBUTOR WAVE WASHER 5.SPEEDOMETER NEEDLE FOR FLUCTUATION (STICKING OR KINKED CABLE AND/ OR SPEEDO HEAD WILL CAUSE VEHICLE SPEED SENSOR (VSS) TO ENGAGE - DISENGAGE TCC) 6.EVAPORATIVE EMISSION CONTROL SYSTEM (EECS) - PURGE SOLENOID OPERATION - HOSES AND CORRECT HOSE CONNECTIONS - CANISTER VENT VALVE OPERATION HESITATION CHECK LIST 1.EGR VALVE SYSTEM OPERATION 2.ACCELERATOR PUMP SYSTEM OPERATION - INCLUDES CHECKING DISCHARGE CHECK BALL SEATING 3.VACUUM HOSES, FITTINGS AND CONNECTIONS 4.IGNITION TIMING 5.CARBURETOR FLOAT LEVEL 6.C-3 WIRING PROXIMITY TO HIGH VOLTAGE WIRING 7.EFE SYSTEM OPERATION 8.T.A.C. SYSTEM OPERATION 9.CARBURETOR FOR LEAN OPERATION 10.OVERHEATING - COOLING SYSTEM PROBLEM 11.INCORRECT SPARK PLUGS 12.BAD FUEL 13.EGR OVERRIDE RELAY CIRCUIT 14.MAP/BARO SENSOR OPERATION

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.