What Is the Distributor Cap Firing Order?

The distributor cap firing order defines the order in which the wires from the distributor cap need to be attached to the cylinders of a vehicle's engine to achieve the correct firing order. Different manufacturers and engines use different firing orders, and connecting the wires incorrectly may cause engine damage.

One issue that requires special attention when attaching wires from the distributor cap to each spark plug in an engine is the direction of rotation of the distributor cap. Different distributor caps may fire in clockwise or counter-clockwise sequence, and the directionality of the distributor cap is not necessarily constant even between different engines made by the same manufacturer.