As you fail to mention year and engine size, I will assume it is a 3.8 V6. Firing order for the 3.8 is 1-6-5-4-3-2
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Firing order is: 1,6,5,4,3,2. Got this from my 19997 LeSabre Owners's Manual.
The firing order for a 1985 Buick LeSabre 5.0L is 1-8-4-3-6-5-7-2. This same firing order is used throughout the 1982-1985 Buick LeSabre's with a 5.0L engine.
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The firing order is stamped into the block, usually on the front side.
the firing order is 1,3,5,2,4,6
1-6-5-4-3-2
1-6-5-4-3-2
1,4,2,3
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