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NOTE: Timing specifications are listed on the Vehicle Emissions Control Information label under the hood. Always follow the Vehicle Emissions Control Information label procedures first before using the following procedure.PROCEDURE: Set timing under the following conditions:
Connect timing light and adjust as necessary by loosening hold down bolt and rotating distributor. For specification, refer to SPECIFICATIONS/ELECTRICAL AND ELECTRONIC SPECIFICATIONS/TIMING SPECIFICATIONS. Tighten hold down and recheck the timing. Stop the engine and connect SET TIMING connector. Clear ECM trouble code by disconnecting ECM power source.NOTE: Dual timing scribes are on the 4.3L engine balancers. They line up with the timing indicators at one o'clock and four o'clock positions. Use the one o'clock position.
Notes:  At idle.
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