Lumpy8

Why does Ford use two different type of plugs in their 3.8 V-6?

I have a 1999 Mustang that has Cylinders 1-2-3 are "EG" Cylinders 4-5-6 are "E"

I have installed Autolight Platinum's #AP765

Is this going to create problems?

Lumpy8

I'll answer my own question as to help out some other person!

Here is some info that might help you......Many Ford engines come from the factory with different platinum spark plugs on the left and right sides of the engine. On a 2000 3.8L V6 you will find platinum plugs marked AWSF-42E on the LH side (cylinders 1,2,3) and AWSF-42EG on the RH side (cylinders 4,5,6). They appear to have different electrodes. Why is this?

Ford does it to take advantage of the "waste spark ignition system" on our cars, in which there is one coil for each pair of spark plugs. One half of the plugs see a different polarity from the other half.

Ford Engine Cylinders Firing Order
1.9L 4 1 3 4 2
2.3L 4 1 3 4 2
3.8L 1 4 2 5 3 6
4.6L 8 1 3 7 2 6 5 4 8
4.6L 32 Valve 8 1 3 7 2 6 5 4 8


The chart above illustrates the firing orders and polarities for Ford waste spark ignition systems. The red numbers are positive firing spark plugs. The blue numbers are negative firing spark plugs.

These differing polarities cause the spark plug electrode metal (platinum) to erode differently, depending on the direction of the current flow of the spark. On one side of the engine metal is transferred from the tip to the electrode. On the other side it goes from electrode to tip. This allows Ford to save a tiny bit of platinum on each plug installed at the factory by using plugs with only a platinum tip on one side and plugs with only a platinum electrode on the other.

jwko

I don't see a problem. Ford recommends AWSF-42EE or you could use a copper plug AWSF-42C