CAMPAIGN:IMPROPERLY MACHINED CYLINDER HEADS. Pontiac Firebird 1998

NOTE: GM Canada version located below U.S. version.

********************* U.S. Version

PRODUCT CAMPAIGNS 98022 JUNE, 1998

PRODUCT RECALL CAMPAIGN

CUSTOMER SATISFACTION CAMPAIGN

SUBJECT: 98022 - IMPROPERLY MACHINED CYLINDER HEADS

MODELS: 1998 CHEVROLET CORVETTES AND CAMAROS AND PONTIAC FIREBIRDS

GENERAL MOTORS HAS DECIDED THAT CERTAIN 1998 CHEVROLET CORVETTE AND CAMARO AND PONTIAC FIREBIRD MODEL VEHICLES EQUIPPED WITH 5.7L (LS1) ENGINES MAY HAVE AN EXHAUST GAS LEAK BETWEEN THE SPARK PLUG(S) AND THE CYLINDER HEAD BECAUSE OF IMPROPER MACHINING OF THE CYLINDER HEAD. THE LEAK(S) MAY CAUSE NOISE AND, IF NOT CORRECTED, COULD RESULT IN ENGINE DAMAGE FROM PREIGNITION.

TO PREVENT THE POSSIBILITY OF THIS CONDITION OCCURRING, DEALERS ARE TO INSPECT THE ENGINES FOR THE BUILD DATE OF THE CYLINDER HEADS. IF THE CYLINDER HEADS ARE STAMPED WITH BUILD DATES OF 02/21/98 THROUGH 03/13/98, THE SPARK PLUG SEATING AREA SHOULD BE REPAIRED PER THE ATTACHED SERVICE PROCEDURE.

VEHICLES INVOLVED

INVOLVED ARE CERTAIN 1998 CHEVROLET CORVETTE AND CAMARO AND PONTIAC FIREBIRD MODEL VEHICLES EQUIPPED WITH 5.7L (LS1) ENGINES AND BUILT WITHIN THE FOLLOWING VIN BREAKPOINTS:

YEAR DIVISION MODEL PLANT CODE FROM THROUGH 1998 CHEVROLET CORVETTE BOWLING GREEN "5" W5120633 W5123548 1998 CHEVROLET CAMARO ST. THERESE "2" W2133255 W2138721 1998 PONTIAC FIREBIRD ST. THERESE "2" W2219643 W2223082

NOTICE: DEALERS SHOULD CONFIRM VEHICLE ELIGIBILITY THROUGH VISS (VEHICLE INFORMATION SERVICE SYSTEM) PRIOR TO BEGINNING CAMPAIGN REPAIRS. NOT ALL VEHICLES WITHIN THE ABOVE BREAKPOINTS MAY BE INVOLVED.

INVOLVED VEHICLES HAVE BEEN IDENTIFIED BY VEHICLE IDENTIFICATION NUMBER. COMPUTER LISTINGS CONTAINING THE COMPLETE VEHICLE IDENTIFICATION NUMBER, CUSTOMER NAME AND ADDRESS DATA HAVE BEEN PREPARED, AND ARE BEING FURNISHED TO INVOLVED DEALERS WITH THE CAMPAIGN BULLETIN. THE CUSTOMER NAME AND ADDRESS DATA FURNISHED WILL ENABLE DEALERS TO FOLLOW-UP WITH CUSTOMERS INVOLVED IN THIS CAMPAIGN. ANY DEALER NOT RECEIVING A COMPUTER LISTING WITH THE CAMPAIGN BULLETIN HAS NO INVOLVED VEHICLES CURRENTLY ASSIGNED.

THESE DEALER LISTINGS MAY CONTAIN CUSTOMER NAMES AND ADDRESSES OBTAINED FROM STATE MOTOR VEHICLE REGISTRATION RECORDS. THE USE OF SUCH MOTOR VEHICLE REGISTRATION DATA FOR ANY OTHER PURPOSE IS A VIOLATION OF LAW IN SEVERAL STATES. ACCORDINGLY, YOU ARE URGED TO LIMIT THE USE OF THIS LISTING TO THE FOLLOW-UP NECESSARY TO COMPLETE THIS CAMPAIGN.

PARTS INFORMATION

PARTS REQUIRED TO COMPLETE THIS CAMPAIGN ARE TO BE OBTAINED FROM GENERAL MOTORS SERVICE PARTS OPERATIONS (GMSPO). PLEASE REFER TO YOUR "INVOLVED VEHICLES LISTING" PRIOR TO ORDERING REQUIREMENTS. NORMAL ORDERS SHOULD BE PLACED ON A DRO = DAILY REPLENISHMENT ORDER. AN EMERGENCY REQUIREMENT SHOULD BE ORDERED ON A CSO = CUSTOMER SPECIAL ORDER.

PART NUMBER DESCRIPTION QUANTITY/VEHICLE 12553617 GASKET - SECONDARY AIR INJECTION PIPE 2-CAMARO/FIREBIRD NONE-CORVETTE CUSTOMER NOTIFICATION

CUSTOMERS WILL BE NOTIFIED OF THIS CAMPAIGN ON THEIR VEHICLES BY GENERAL MOTORS (SEE COPY OF TYPICAL CUSTOMER LETTER INCLUDED WITH THIS BULLETIN - ACTUAL DIVISIONAL LETTER MAY VARY SLIGHTLY).

DEALER CAMPAIGN RESPONSIBILITY

ALL UNSOLD NEW VEHICLES IN DEALERS' POSSESSION AND SUBJECT TO THIS CAMPAIGN MUST BE HELD AND INSPECTED/REPAIRED PER THE SERVICE PROCEDURE OF THIS CAMPAIGN BULLETIN BEFORE CUSTOMERS TAKE POSSESSION OF THESE VEHICLES.

DEALERS ARE TO SERVICE ALL VEHICLES SUBJECT TO THIS CAMPAIGN AT NO CHARGE TO CUSTOMERS, REGARDLESS OF MILEAGE, AGE OF VEHICLE, OR OWNERSHIP, FROM THIS TIME FORWARD.

CUSTOMERS WHO HAVE RECENTLY PURCHASED VEHICLES SOLD FROM YOUR VEHICLE INVENTORY, AND FOR WHICH THERE IS NO CUSTOMER INFORMATION INDICATED ON THE DEALER LISTING, ARE TO BE CONTACTED BY THE DEALER. ARRANGEMENTS ARE TO BE MADE TO MAKE THE REQUIRED CORRECTION ACCORDING TO THE INSTRUCTIONS CONTAINED IN THIS BULLETIN. THIS COULD BE DONE BY MAILING TO SUCH CUSTOMERS A COPY OF THE APPROPRIATE DIVISIONAL CUSTOMER LETTER ACCOMPANYING THIS BULLETIN. CAMPAIGN FOLLOW-UP CARDS SHOULD NOT BE USED FOR THIS PURPOSE, SINCE THE CUSTOMER MAY NOT AS YET HAVE RECEIVED THE NOTIFICATION LETTER.

IN SUMMARY, WHENEVER A VEHICLE SUBJECT TO THIS CAMPAIGN ENTERS YOUR VEHICLE INVENTORY, OR IS IN YOUR DEALERSHIP FOR SERVICE IN THE FUTURE, PLEASE TAKE THE STEPS NECESSARY TO BE SURE THE CAMPAIGN CORRECTION HAS BEEN MADE BEFORE SELLING OR RELEASING THE VEHICLE.

SPECIAL TOOL

DURING THE WEEK OF JUNE 8, 1998, EACH DEALER WITH AFFECTED VEHICLES OF RECORD WILL BE SHIPPED A SPECIAL TOOL FOR FORMING A SPARK PLUG SEAT, J-43676, FOR USE AS NEEDED IN THIS CAMPAIGN. THIS TOOL IS BEING FURNISHED AT NO CHARGE. NOTE: THIS TOOL WILL DRESS 200 SPARK PLUG SEATS.

SERVICE PROCEDURE

1. INSPECT THE CYLINDER HEADS FOR THE PROPER DATE CODE. THE DATE CODE IS LOCATED ON THE EXHAUST MANIFOLD DECK OF THE CYLINDER HEAD (LEFT FRONT AREA FOR THE LEFT SIDE OF THE ENGINE, RIGHT REAR AREA FOR THE RIGHT SIDE OF THE ENGINE). ACCESS TO THE RIGHT CYLINDER HEAD DATE CODE AREA OF THE CAMARO/FIREBIRD MAY BE EASIER TO VIEW IF THE VEHICLE IS ON A HOIST. IF THE CYLINDER HEADS ARE NOT WITHIN THE 02/21/98 THROUGH 03/13/98 DATE CODES, PROCEED TO STEP 38. IF THE CYLINDER HEADS ARE WITHIN THE 02/21/98 THROUGH 03/13/98 DATE CODES, PROCEED TO STEP 2. (SEE FIGURE 1)

FIGURE 1

2. DISCONNECT THE NEGATIVE BATTERY CABLE.

3. REMOVE THE ENGINE BEAUTY COVERS (CORVETTE ONLY).

4. REMOVE ALL THE SPARK PLUG WIRES. NOTICE: ALLOW THE ENGINE TO COOL TO ROOM TEMPERATURE BEFORE REMOVING THE SPARK PLUGS. THREAD DAMAGE MAY OCCUR.

5. SEPARATE THE LEFT AIR CLAMP AND HOSE FROM THE CHECK VALVE (CORVETTE ONLY).

6. REMOVE LEFT AND RIGHT AIR PIPES FROM THE EXHAUST MANIFOLDS (CAMARO/FIREBIRD ONLY).

7. IN ORDER TO GAIN ACCESS TO SPARK PLUG NUMBER EIGHT (8), REMOVE IGNITION COILS SIX (6) AND EIGHT (8) (RIGHT BANK), FROM THE VALVE ROCKER ARM COVER (CAMARO/FIREBIRD ONLY).

8. LOOSEN EACH INDIVIDUAL SPARK PLUG UNTIL NO SEAT CONTACT., TIGHTEN EACH INDIVIDUAL SPARK PLUG TO 40 NM (30 LB FT).

9. LOOSEN EACH INDIVIDUAL SPARK PLUG UNTIL NO SEAT CONTACT. RETIGHTEN THE SPARK PLUGS TO 20 NM (15 LB FT).

10. REINSTALL IGNITION COILS SIX (6) AND EIGHT (8). TIGHTEN THE COIL MOUNTING BOLTS TO 12 NM (106 LB IN) (CAMARO/FIREBIRD ONLY).

11. REINSTALL THE AIR PIPES TO THE EXHAUST MANIFOLDS WITH NEW GASKETS. TIGHTEN THE BOLTS TO 12 NM (106 LB IN) (CAMARO/FIREBIRD ONLY).

12. RECONNECT THE LEFT AIR HOSE AND CLAMP TO THE CHECK VALVE (CORVETTE ONLY).

13. REINSTALL THE SPARK PLUG WIRES.

14. RECONNECT THE NEGATIVE BATTERY CABLE.

15. RUN THE ENGINE, LISTEN FOR AN AIR/EXHAUST LEAK AT EACH SPARK PLUG LOCATION USING A STETHOSCOPE/LISTENING DEVICE.

NOTE: MODIFY THE STETHOSCOPE OR LISTENING DEVICE (IF REQUIRED). IF THE LISTENING DEVICE IS EQUIPPED WITH A METAL PROBE, IT MUST BE REMOVED AND REPLACED WITH A RUBBER TYPE HOSE.

CAUTION:

TO AVOID INJURY OR ELECTRICAL SHOCK, THE STETHOSCOPE MUST BE MODIFIED.

16. IF AN AIR/EXHAUST LEAK IS DETECTED AT ANY OF THE SPARK PLUG LOCATIONS, PROCEED TO STEP 17. IF NO LEAK IS DETECTED PROCEED TO STEP 36.

17. DISCONNECT THE NEGATIVE BATTERY CABLE.

18. IF AN AIR/EXHAUST LEAK IS PRESENT ON THE LEFT HAND CYLINDERS FIVE (5) OR SEVEN (7), SEPARATE THE LEFT AIR CLAMP AND HOSE FROM THE CHECK VALVE (CORVETTE ONLY).

19. IF AN AIR/EXHAUST LEAK IS PRESENT, REMOVE THE AIR PIPE THAT IS ASSOCIATED WITH THE LEAKING SPARK PLUG LOCATION (CAMARO/FIREBIRD ONLY).

NOTICE: ALLOW THE ENGINE TO COOL TO ROOM TEMPERATURE BEFORE REMOVING THE SPARK PLUGS. THREAD DAMAGE MAY OCCUR.

20. REMOVE THE SPARK PLUG WIRE THAT IS ASSOCIATED WITH THE LEAKING SPARK PLUG LOCATION.

21. IF REQUIRED, REMOVE IGNITION COILS SIX (6) AND EIGHT (8) (RIGHT BANK) IN ORDER TO GAIN ACCESS TO SPARK PLUG NUMBER EIGHT (8) (CAMARO/FIREBIRD ONLY).

22. REMOVE THE SPARK PLUG(S) ASSOCIATED WITH THE LEAKING SPARK PLUG LOCATION(S).

23. INSTALL THE PILOT TOOL (FIGURE 2, ITEM 2) INTO THE SPARK PLUG HOLE. AFTER INITIAL THREAD ENGAGEMENT, ROTATE THE TOOL TEN (10) FULL TURNS.

NOTICE: THE PILOT IS INSTALLED TEN (10) FULL TURNS TO ENSURE PROPER DEPTH/TRAVEL FOR THE DRESSING/BUSHING TOOL. AN OVER-INSTALLED PILOT TOOL MAY FALL INTO THE CYLINDER. (SEE FIGURE 2)

24. POSITION THE DRESSING/BUSHING TOOL (FIGURE 2, ITEM 1) OVER THE PILOT TOOL (FIGURE 2, ITEM 2).

25. ROTATE THE DRESSING/BUSHING TOOL EIGHT (8) TO TEN (10) COMPLETE TURNS. THE TOOL BUSHING WILL DETERMINE THE DEPTH/ TRAVEL OF THE DRESSER.

FIGURE 2

26. REMOVE THE DRESSING/BUSHING TOOL FROM THE PILOT (DO NOT REMOVE THE PILOT).

27. USE SHOP AIR OR A SHOP VACUUM TO REMOVE ALL DEBRIS FROM THE SPARK PLUG CAVITY AND DRESSER HEAD.

28. REMOVE THE PILOT TOOL FROM THE SPARK PLUG HOLE.

29. REINSTALL THE SPARK PLUG(S), TIGHTEN TO 40 NM (30 LB FT).

30. LOOSEN THE SPARK PLUG(S) UNTIL NO SEAT CONTACT. RETIGHTEN THE SPARK PLUG(S) TO 20 NM (15 LB FT).

31. IF REQUIRED, REINSTALL IGNITION COILS SIX (6) AND EIGHT (8). TIGHTEN THE COIL BOLTS TO 12 NM (106 LB IN)(CAMARO/FIREBIRD ONLY).

32. IF REQUIRED, REINSTALL THE APPLICABLE AIR PIPE AND GASKET TO THE EXHAUST MANIFOLD. THE NEW GASKET USED IN STEP 12 MAY BE REUSED. TIGHTEN THE BOLTS TO 12 NM (106 LB IN) (CAMARO/FIREBIRD ONLY).

33. IF REQUIRED, RECONNECT THE LEFT AIR HOSE AND CLAMP TO THE CHECK VALVE (CORVETTE ONLY).

34. REINSTALL THE APPLICABLE SPARK PLUG WIRE(S).

35. RECONNECT THE NEGATIVE BATTERY CABLE.

36. USING A TECH II, RUN THE ENGINE AND CHECK FOR CYLINDER MISFIRE AND AIR SYSTEM FUNCTION.

37. REINSTALL THE BEAUTY COVERS (CORVETTE ONLY).

38. INSTALL THE GM CAMPAIGN IDENTIFICATION LABEL.

CAMPAIGN IDENTIFICATION LABEL

EACH VEHICLE CORRECTED IN ACCORDANCE WITH THE INSTRUCTIONS OUTLINED IN THIS PRODUCT CAMPAIGN BULLETIN WILL REQUIRE A "CAMPAIGN IDENTIFICATION LABEL". EACH LABEL PROVIDES A SPACE TO INCLUDE THE CAMPAIGN NUMBER AND THE FIVE (5) DIGIT DEALER CODE OF THE DEALER PERFORMING THE CAMPAIGN SERVICE. THIS INFORMATION MAY BE INSERTED WITH A TYPEWRITER OR A BALL POINT PEN.

EACH "CAMPAIGN IDENTIFICATION LABEL" IS TO BE LOCATED ON THE RADIATOR CORE SUPPORT IN AN AREA WHICH WILL BE VISIBLE WHEN THE VEHICLE IS BROUGHT IN BY THE CUSTOMER FOR PERIODIC SERVICING. WHEN INSTALLING THE CAMPAIGN IDENTIFICATION LABEL, BE SURE TO PULL THE TAB TO ALLOW ADHESION OF THE CLEAR PROTECTIVE COVERING. ADDITIONAL CAMPAIGN IDENTIFICATION LABELS CAN BE OBTAINED FROM VISPAC INCORPORATED BY CALLING 1-800-269-5100 (MONDAY-FRIDAY, 8:00 A.M. TO 4:30 P.M. EST). ASK FOR ITEM NUMBER S-1015 WHEN ORDERING.

APPLY THE "CAMPAIGN IDENTIFICATION LABEL" ONLY ON A CLEAN, DRY SURFACE.

CLAIM INFORMATION

SUBMIT A PRODUCT CAMPAIGN CLAIM WITH THE INFORMATION INDICATED BELOW:

PART FAILED PARTS LABOR LABOR NET REPAIR PERFORMED COUNT PART NO. ALLOW CC-FC OP * HOURS ITEM INSPECT CYLINDER HEAD DATE - NO REPAIR NECESSARY -- -- -- MA-96 V0167 0.2

INSPECT CYLINDER HEAD DATE - RETORQUE SPARK PLUGS ONLY

-CAMARO/FIREBIRD CAMARO/FIREBIRD (2) 12553617 ** MA-96 V0168 1.1

-CORVETTE CORVETTE - NO -- 0.8

INSPECT CYLINDER HEAD DATE - RETORQUE ALL SPARK PLUGS AND DRESS SPARK PLUG SEAT AREA ON LEFT BANK CYLINDER HEAD ONLY

-CAMARO/FIREBIRD CAMARO/FIREBIRD (2) 12553617 -- ** MA-96 V0169 1.6

-CORVETTE CORVETTE - NO 1.4

INSPECT CYLINDER HEAD DATE - RETORQUE ALL SPARK PLUGS AND DRESS SPARK PLUG SEAT AREA ON RIGHT BANK CYLINDER HEAD ONLY

-CAMARO/FIREBIRD CAMARO/FIREBIRD (2) 12553617 -- ** MA-96 V0179 2.0

-CORVETTE CORVETTE - NO 1.3

INSPECT CYLINDER HEAD DATE - RETORQUE ALL SPARK PLUGS AND DRESS SPARK PLUG SEAT AREA ON LEFT AND RIGHT BANK CYLINDER HEADS

-CAMARO/FIREBIRD CAMARO/FIREBIRD (2) 12553617 -- ** MA-96 V0182 2.5

CORVETTE - NO 1.9

* FOR CAMPAIGN ADMINISTRATIVE ALLOWANCE, ADD 0.1 HOURS TO THE "LABOR HOURS".

** THE "PARTS ALLOWANCE" SHOULD BE THE SUM TOTAL OF THE CURRENT GMSPO DEALER NET PRICE PLUS 40% FOR GASKETS NEEDED TO COMPLETE THE REPAIR ON CAMARO/ FIREBIRD ONLY.

REFER TO THE GENERAL MOTORS CORPORATION CLAIMS PROCESSING MANUAL FOR DETAILS ON PRODUCT CAMPAIGN CLAIM SUBMISSION.

FIGURES: 2

Object Number: 336946 Size: FS

Object Number: 336948 Size: FS

GM BULLETINS ARE INTENDED FOR USE BY PROFESSIONAL TECHNICIANS, NOT A "DO-IT-YOURSELFER". THEY ARE WRITTEN TO INFORM THESE 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 TOOLS, EQUIPMENT, 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 YOUR DEALER/RETAILER FOR INFORMATION ON WHETHER YOUR VEHICLE MAY BENEFIT FROM THE INFORMATION.

WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION

98022

(SAMPLE OF NOTIFICATION USED)

JUNE, 1998

DEAR <DIVISION(S)> CUSTOMER:

THIS NOTICE IS SENT TO INFORM YOU OF A RECALL CAMPAIGN THAT INCLUDES YOUR VEHICLE.

REASON FOR THIS RECALL: GENERAL MOTORS HAS DECIDED THAT CERTAIN 1998 CHEVROLET CORVETTE AND CAMARO AND PONTIAC FIREBIRD MODEL VEHICLES EQUIPPED WITH 5.7L ENGINES MAY HAVE AN EXHAUST GAS LEAK BETWEEN THE SPARK PLUG(S) AND THE CYLINDER HEAD BECAUSE OF IMPROPER MACHINING OF THE CYLINDER HEAD. THE LEAK(S) MAY CAUSE NOISE AND, IF NOT CORRECTED, COULD RESULT IN ENGINE DAMAGE FROM PREIGNITION.

WHAT WILL BE DONE: TO PREVENT THE POSSIBILITY OF THIS CONDITION OCCURRING, YOUR DEALER WILL INSPECT YOUR ENGINE FOR THE BUILD DATE OF THE CYLINDER HEADS. IF THE CYLINDER HEADS ARE STAMPED WITH BUILD DATES OF 02/21/98 THROUGH 03/13/98, THE SPARK PLUG SEATING AREA WILL BE REPAIRED BY YOUR DEALER. THIS SERVICE WILL BE PERFORMED FOR YOU AT NO CHARGE.

CONTACTING YOUR DEALER: PLEASE CONTACT YOUR DEALER AS SOON AS POSSIBLE TO ARRANGE A SERVICE DATE AND TO ASSURE PARTS AVAILABILITY. INSTRUCTIONS FOR MAKING THIS CORRECTION HAVE BEEN SENT TO YOUR DEALER. PLEASE ASK YOUR DEALER IF YOU WISH TO KNOW HOW MUCH TIME WILL BE NEEDED TO SCHEDULE, PROCESS AND REPAIR YOUR VEHICLE.

IF YOU EXPERIENCE ANY TROUBLE SCHEDULING YOUR VEHICLE OR YOU HAVE ANY QUESTIONS REGARDING THIS RECALL ACTION, PLEASE CONTACT THE APPROPRIATE CUSTOMER ASSISTANCE CENTER AT THE LISTED NUMBER BELOW:

DIVISION

NUMBER DEAF, HEARING IMPAIRED OR SPEECH IMPAIRED *

CHEVROLET 1-800-222-1020 1-800-833-2438

PONTIAC 1-800-762-2737 1-800-833-7668

* UTILIZES TELECOMMUNICATION DEVICES FOR THE DEAF/TEXT TELEPHONES (TDD/TTY)

CUSTOMER REPLY CARD: THE ENCLOSED CUSTOMER REPLY CARD IDENTIFIES YOUR VEHICLE. PRESENTATION OF THIS CARD TO YOUR DEALER WILL ASSIST IN MAKING THE NECESSARY CORRECTION IN THE SHORTEST POSSIBLE TIME. IF YOU NO LONGER OWN THIS VEHICLE, PLEASE LET US KNOW BY COMPLETING THE POSTAGE PAID REPLY CARD AND RETURNING IT TO US.

WE ARE SORRY TO CAUSE YOU THIS INCONVENIENCE; HOWEVER, WE HAVE TAKEN THIS ACTION IN THE INTEREST OF YOUR CONTINUED SATISFACTION WITH OUR PRODUCTS.

<DIVISION(S)> GENERAL MOTORS CORPORATION ENCLOSURE

******************************************************************** ************************ GM Canada Version *********************** ********************************************************************

CUSTOMER SATISFACTION CAMPAIGN

SUBJECT: CAMPAIGN 98022 - EUROPERLY MACHINED CYLINDER HEADS

MODELS: 1998 CHEVROLET CORVETTES AND CAMAROS AND PONTIAC FIREBIRDS

DEFECT INVOLVED

General Motors of Canada Limited has decided that certain 1998 Chevrolet Corvette and Camaro and Pontiac Firebird model vehicles equipped with 5.7L (LS1) engines may have an exhaust gas leak between the spark plug(s) and the cylinder head because of improper machining of the cylinder head. The leak(s) may cause noise and, if not corrected, could result in engine damage from preignition.

To prevent the possibility of this condition occurring, dealers are to inspect the engines for the build date of the cylinder heads.If the cylinder heads are stamped with build dates of 02/21/98 through 03/13/98, the spark plug seating area should be repaired per the Service Procedure in this bulletin.

VEHICLES INVOLVED

Involved are certain 1998 Chevrolet Corvette and Camaro and Pontiac Firebird model vehicles equipped with 5.7L (LS1) engines and built within the following VIN breakpoints:

PLANT YEAR DIVISION MODEL PLANT CODE FROM THROUGH

1998 Chevrolet Corvette Bowling Green "5" W5120633 W5123548 1998 Chevrolet Camaro Ste-Therese "2" W2133255 W2138721 1998 Pontiac Firebird Ste-Therese "2" W2219643 W2223082

NOTE: PLEASE CHECK DCS SCREEN 445 OR YOUR V.I.N. LISTING BEFORE PERFORMING CAMPAIGN TO ENSURE THAT THE VEHICLE IS AFFECTED. ONLY AFFECTED VIN'S WILL BE PAID.

Involved vehicles have been identified by Vehicle Identification Number. Computer listings containing the complete Vehicle Identification Number, customer name and address data have been prepared,and are being furnished to involved dealers with the campaign bulletin. The customer name and address data furnished will enable dealers to follow-up with customers involved in this campaign. Any dealer not receiving a computer listing with the campaign bulletin has no involved vehicles currently assigned.

These dealer listings may contain customer names and addresses obtained from the Inter-Provincial Records. The use of such motor vehicle registration data for any other purpose is a violation of provincial laws. Accordingly, you are urged to limit the use of this listing to the follow-up necessary to complete this campaign.

PARTS INFORMATION

Parts required to complete this campaign are to be obtained from General Motors Service Parts Operations (GMSPO). Please refer to your "involved vehicles listing" prior to ordering requirements.

Part Number Description Quantity/Vehicle

12553617 Secondary Air Injection Pipe Gasket 2-Camaro/Firebird None-Corvette

CUSTOMER NOTIFICATION

All customers of record at the time of campaign release are shown on the attached computer listing and have been notified by first class mail from General Motors (see copy of customer letter included with this bulletin).

DEALER CAMPAIGN RESPONSIBILITY

All unsold new vehicles in dealer's possession and subject to this campaign must be held and inspected/repaired per the service procedure of this campaign bulletin before customers take possession of these vehicles.

Dealers are to service all vehicles subject to this campaign at no charge to customers, regardless of mileage, age of vehicle, or ownership, from this time forward.

Customers who have recently purchased vehicles sold from your vehicle inventory, and for which there is no customer information indicated on the dealer listing, are to be contacted by the dealer. Arrangements are to be made to make the required correction according to the instructions contained in this bulletin. This could be done by mailing to such customers a copy of the appropriate customer letter accompanying this bulletin.

In summary, whenever a vehicle subject to this campaign enters your vehicle inventory, or is in your dealership for service in the future, you must take the steps necessary to be sure the campaign correction has been made before selling or releasing the vehicle.

SPECIAL TOOL

Each dealer with affected vehicles of record will be shipped at no charge, along with this bulletin, a special tool for forming a spark plug seat, J43676, for use as needed in this campaign. This tool will dress 200 spark plug seats.

SERVICE PROCEDURE

1. Inspect the cylinder heads for the proper date code. The date code is located on the exhaust manifold deck of the cylinder head (left front area for the left side of the engine, right rear area for the right side of the engine). Access to the right cylinder head date code area of the Camaro/Firebird may be easier to view if the vehicle is on a hoist. If the cylinder heads are not within the 02/21/98 through 03/13/98 date codes, proceed to step 38. If the cylinder heads are within the 02/21/98 through 03/13/98 date codes, proceed to step 2. See Figure 1.

2. Disconnect the negative battery cable.

3. Remove the engine beauty covers (Corvette only).

4. Remove all the spark plug wires.

NOTICE: Allow the engine to cool to room temperature before removing the spark plugs. Thread damage may occur.

5. Separate the left AIR clamp and hose from the check valve (Corvette only).

6. Remove left and right AIR pipes from the exhaust manifolds (Camaro/Firebird only).

7. In order to gain access to spark plug number eight (8), remove ignition coils six (6) and eight (8) (right bank),from the valve rocker arm cover (Camaro/Firebird only).

8. Loosen each individual spark plug until no seat contact. Tighten each individual spark plug to 40 N-m (30 lb. ft.).

9. Loosen each individual spark plug until no seat contact. Retighten the spark plugs to 20 N-m (15 lb. ft).

10. Reinstall ignition coils six (6) and eight (8). Tighten the coil mounting bolts to 12 N-m (106 lb. in.) (Camaro/Firebird only).

11. Reinstall the AIR pipes to the exhaust manifolds with NEW gaskets. Tighten the bolts to 12 N-m (106 lb. in.) (Camaro/Firebird only).

12. Reconnect the left AIR hose and clamp to the check valve (Corvette only).

13. Reinstall the spark plug wires.

14. Reconnect the negative battery cable.

15. Run the engine, listen for an air/exhaust leak at each spark plug location using a stethoscope/listening device.

NOTE: Modify the stethoscope or listening device (if required). If the listening device is equipped with a metal probe, it must be removed and replaced with a rubber type hose.

CAUTION:

To avoid injury or electrical shock, the stethoscope must be modified.

16. If an air/exhaust leak is detected at any of the spark plug locations, proceed to step 17. If no leak is detected proceed to step 36.

17. Disconnect the negative battery cable.

18. If an air/exhaust leak is present on the left hand cylinders five (5) or seven (7), separate the left AIR clamp and hose from the check valve (Corvette only).

19. If an air/exhaust leak is present, remove the AIR pipe that is associated with the leaking spark plug location (Camaro/Firebird only).

NOTICE: Allow the engine to cool to room temperature before removing the spark plugs. Thread damage may occur.

20. Remove the spark plug wire that is associated with the leaking spark plug location.

21. If required, remove ignition coils six (6) and eight (8) (right bank) in order to gain access to spark plug number eight (8) (Camaro/Firebird only).

22. Remove the spark plug(s) associated with the leaking spark plug location(s).

23. Install the pilot tool (Figure 2, Item 2) into the spark plug hole. After initial thread engagement, rotate the tool ten (10) full turns.

NOTICE: The pilot is installed ten (10) full turns to ensure proper depth/travel for the dressing/bushing tool. An over-installed pilot tool may fall into the cylinder (see Figure 2).

24. Position the dressing/bushing tool (Figure 2, Item 1) over the pilot tool (Figure 2, Item 2).

25. Rotate the dressing/bushing tool eight (8) to ten (10) complete turns. The tool bushing will determine the depth/travel of the dresser.

26. Remove the dressing/bushing tool from the pilot (DO NOT REMOVE THE PILOT).

27. Use shop air or a shop vacuum to remove all debris from the spark plug cavity and dresser head.

28. Remove the pilot tool from the spark plug hole.

29. Reinstall the spark plug(s), tighten to 40 N-m (30 lb. ft.).

30. Loosen the spark plug(s) until no seat contact. Retighten the spark plug(s) to 20 N-m (15 lb. ft.).

31. If required, reinstall ignition coils six (6) and eight (8). Tighten the coil bolts to 12 N-m (106 lb. in.) (Camaro/Firebird only).

32. If required, reinstall the applicable AIR pipe and gasket to the exhaust manifold. The NEW gasket used in step 12 may be reused. Tighten the bolts to 12 N-m (106 lb. in.) (Camaro/Firebird only).

33. If required, reconnect the left AIR hose and clamp to the check valve (Corvette only).

34. Reinstall the applicable spark plug wire(s).

35. Reconnect the negative battery cable.

36. Using a Tech II, run the engine and check for cylinder misfire and AIR system function.

37. Reinstall the beauty covers (Corvette only).

38. Install Campaign Identification Label.

CAMPAIGN IDENTIFICATION LABEL

Each vehicle corrected in accordance with the instructions outlined in this Product Campaign Bulletin will require a "Campaign Identification Label." Each label provides a space to include the campaign number and the five (5) digit dealer code of the dealer performing the campaign service. This information may be inserted with a typewriter or a ball point pen.

Each "Campaign Identification Label" is to be located on the radiator core support in an area which will be visible when the vehicle is brought in by the customer for periodic servicing. Additional Campaign Identification Labels can be obtained from DGN by calling 1-800-668-5539 (Monday-Friday, 8:00 am. to 5:00 p.m. EST). Ask for Item Number GMT 91 when ordering.

Apply the "Campaign Identification Label" only on a clean, dry surface.

CLAIM INFORMATION

Submit a Product Campaign Claim with the information indicated below:

* REPAIR PERFORMED PART FAILED PARTS LABOUR LABOUR COUNT PART NO. ALLOW CC-FC 0P HOURS

Inspect Cylinder Head Date - No Repair -- -- -- MA-96 V0167 0.2 Necessary

Inspect Cylinder Head Date - Retorque Spark Plugs Only Camaro/ 12553617 ** MA-96 V0168 1.1 -Camaro/Firebird Firebird - (2)

-Corvette Corvette - No -- 0.8

Inspect Cylinder Head Date - Retorque All Spark Plugs and Dress Spark Plug Seat Area on Left Bank Cylinder Head Only

Camaro/ 12553617 ** MA-96 V0169 1.6 -Camaro/Firebird Firebird - (2)

-Corvette Corvette - No -- 1.4

Inspect Cylinder Head Date - Retorque All Spark Plugs and Dress Spark Plug Seat Area on Right Bank Cylinder Head Only

Camaro/ 12553617 ** MA-96 V0179 2.0 -Camaro/Firebird Firebird - (2)

-Corvette Corvette - No -- 1.3

Inspect Cylinder Head Date - Retorque All Spark Plugs and Dress Spark Plug Seat Area on Left and Right Bank Cylinder Heads

Camaro/ 12553617 ** MA-96 V0182 2.5 -Camaro/Firebird Firebird - (2)

-Corvette Corvette - No -- 1.9

* For Campaign Administrative Allowance,add 0.1 hours to the "Labour Hours".

** The "Parts Allowance" should be the sum total of the current GMSPO Dealer Net price plus 40% for gaskets needed to complete the repair on Camaro/Firebird only.

Refer to the General Motors Claim Processing Manual for details on Product Campaign Claim Submission.

June 1998

Dear General Motors Customer:

General Motors of Canada Limited has decided that certain 1998 Chevrolet Corvette and Camaro and Pontiac Firebird model vehicles equipped with 5.7L engines may have an exhaust gas leak between the spark plug(s) and the cylinder head because of improper machining of the cylinder head. The leak(s) may cause noise and, if not corrected, could result in engine damage from preignition.

To prevent the possibility of this condition occurring, your GM dealer will inspect your engine for the build date of the cylinder heads.If the cylinder heads are stamped with build dates of 02/21/98 through 03/13/98, the spark plug seating area will be repaired by your dealer.

This service will be provided for you at no charge.

Please contact your GM dealer as soon as possible to arrange a service date.

If parts are required, ask your dealer for details regarding their availability. If parts are not in stock, they can be ordered before scheduling your service date.

This letter identifies your vehicle. Presentation of this letter to your dealer will assist their Service personnel in completing the necessary correction to your vehicle in the shortest possible time.

We are sorry to cause you this inconvenience; however, we have taken this action in the interest of your continued satisfaction with our products.

Customer Support Department General Motors of Canada Limited