4.3L, 1, 6, 5, 4, 3, 2.
2.5L, 1, 3, 4, 2.
The firing order should be stamped on the engine block right on top in front of the carborator.
18436572
165432
For a 1991 Chevy S10 2.5L engine the firing order is: 1-3-4-2 . The distributor rotates clockwise.
1342 ccw
1324
The firing order should be 1-8-4-3-6-5-7-2.
165432 #1 cylinder is left front
The firing order should be 1-8-4-3-6-5-7-2.
When troubleshooting problems within an engine, it can help to know the firing order. The firing order of a 1991 Chevy Lumina 3.1L is 1-2-3-4-5-6.
Chevy 5.7 L firing order is 1-8-4-3-6-5-7-2 clockwise.
it will be stamped on your intake. all 8 numbers in a random order.