[Image of a distributor cap with the spark plug wires labeled 1-8 in clockwise order.]
The firing order for a 4.9-liter engine is 1-3-7-2-6-5-4-8. This means that spark plug wire #1 should be connected to the distributor cap terminal marked "1", spark plug wire #2 should be connected to the terminal marked "2", and so on.
When the distributor rotor rotates, it will make contact with each of the terminals on the distributor cap in the order shown in the diagram. This will send a high-voltage spark to the corresponding spark plug, which will ignite the air/fuel mixture in the engine cylinder.
It is important to make sure that the distributor cap wires are connected in the correct order. If they are not, the engine will not run properly.
