Hi

I am installing a wire set Motocraft WR6110. Why is one cables boot red and one is black? All the rest are gray.

Thanks

Harry

 

Because those are whatever they had left laying around at the plant when they made the wires.

There's nothing special about them.

 

Hi

10-4

It turned out that #3 original wire on the truck had a red boot. The new wire with the red boot was the same length....so I put it on #3.

Harry

 

The 4.2l v6 utilizes a wasted spark ignition system.... means that when the plugs fire in pairs, they fire on both the exhaust and compression strokes.

The red indicates the first wasted spark that is fired in each sequence of the firing order.

Basically, one half of the plugs see a different polarity from the other half.

Plugs 1, 2, and 3 are positive firing plugs. Plugs 4, 5, and 6 are negative firing plugs.