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Ignition Timing - Inability to Check Timing

Number 87-6 (Gasoline)-48 Date 6/87
Subject: INABILITY TO SET IGNITION TIMING


1987 SUNBIRD MODELS EQUIPPED WITH LT2/LT3 2.0L OHC ENGINE (VIN CODE K AND M)
Early built LT2 and LT3 engines used a crankshaft dampner that could experience an outer "Timing" ring rotation relative to the inner crankshaft drive. The result is the inability to check or set spark timing after miles of customer service.

A new crankshaft dampner pulley, P/N 10083143, repairs the original outer ring slippage. Below are the VIN Codes of potentially affected vehicles.

ENGINE VIN'S
VIN CODE PRIOR TO

K H7566886

M H7567626

Use applicable Labor Operation and Time.