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INFO. ON NEW SPARK PLUGS SPARK PLUG WIRES & BOOTS

REVISION: 01/05/95

THIS BULLETIN IS BEING REVISED TO DESIGNATE 1995 MODEL YEAR USAGE ONLY FOR THE SPARK PLUG WIRES PART NUMBERS CONTAINED IN THIS BULLETIN AND CORRECT THE DESCRIPTION USAGE OF THE SPARK PLUG PART NUMBERS. PLEASE DISCARD BULLETIN 47-61-45 (SECTION 6 - ENGINE). ----------------------------------------------------------------------

SUBJECT: INFORMATION ON NEW SPARK PLUGS, SPARK PLUG WIRES AND BOOTS

MODELS: 1995 CADILLAC ELDORADO, SEVILLE WITH 4.6L ENGINE (VINS 9, Y - RPOS L37, LD8)

1995 CADILLAC CONCOURS WITH 4.6L ENGINE (VIN Y - RPO LD8)

1995 OLDSMOBILE AURORA WITH 4.0L ENGINE (VIN C - RPO L47)

NEW DESIGN SPARK PLUGS AND SPARK PLUG WIRES AND BOOTS WENT INTO PRODUCTION ON 4.6L NORTHSTAR AND 4.0L AURORA ENGINES IN THE 1995 MODEL YEAR. FEATURES OF THESE NEW SPARK PLUGS AND WIRES ARE:

1. THE SPARK PLUGS ARE IDENTIFIED WITH THE CODE AC-929 AND HAVE A "RIBLESS" PORCELAIN INSULATOR.

2. THIS "RIBLESS" INSULATOR AND BOOT DESIGN PROVIDE A BETTER PLUG-TO-BOOT RETENTION.

3. THIS NEW AC-929 SPARK PLUG AND BOOT DESIGN SIGNIFICANTLY REDUCES CARBON TRACKING AND REDUCES ENGINE MISFIRE.

THESE NEW SPARK PLUGS MAY BE USED INTERCHANGEABLY WITH THE PREVIOUS DESIGN AC-900 SPARK PLUGS ON ANY MODEL YEAR 4.0L AND 4.6L ENGINE. THESE NEW SPARK PLUG WIRES CANNOT BE USED ON 1993 AND 1994 MODEL YEAR VEHICLES DUE TO DIFFERENCES IN SPARK PLUG WIRE LENGTHS.

THE SPARK PLUG WIRE BOOTS CONTAIN FHC GREASE AS A LUBRICANT, WHICH WILL LAST THE ENTIRE LIFE OF THE SPARK PLUG WIRE. IF SILICONE TYPE LUBRICANTS ARE ADDED TO FHC COATED SPARK PLUG BOOTS, CARBON TRACKING OF SPARK PLUGS MAY OCCUR.

WHEN ORDERING THESE NEW SPARK PLUG WIRES AND SPARK PLUGS, REFER TO THE FOLLOWING PART NUMBERS:

PART NUMBER DESCRIPTION ----------- ----------- 12096450 SPARK PLUG WIRE SET G CAR 12173402 SPARK PLUG WIRE SET E, K 25161678 AC 929 SPARK PLUGS

PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.

REFER TO THE SERVICE PROCEDURES OUTLINED IN THE APPROPRIATE SERVICE INFORMATION MANUAL WHEN REPLACEMENT OF THE ABOVE MENTIONED COMPONENTS IS NECESSARY.

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