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Ignition - Revised Spark Plug Usage & Gap Information

File In Section: 0 - General Information

Bulletin No.: 73-02-03

Date: August, 1997

SERVICE MANUAL UPDATE

Subject:
Sections OB and 6D4 - Revised Spark Plug Usage and Gap Information

Models:
1991 Chevrolet Lumina
1991 Oldsmobile Cutlass Supreme
1991 Pontiac Grand Prix
with 2.5L or 3.1 L Engine (VINs R, T - RPOs LR8, LH0)

This bulletin is being issued to revise the published spark plug usage and gap information in Sections OB (Maintenance and Lubrication) and 6D4 (Ignition System) of the Service Manual.

The following table contains the correct spark plug usages and appropriate gap.

Engine SparK Plug # Gap
2.5L (VIN R) R43TS6 1.50 mm (0.060")
3.1L (VIN T) R44LTSM 1.14 mm (0.045")