The firing order for the 1999 Ford Windstar 3.8L V6 is 1-6-5-4-3-2.
To correctly connect the spark plug wires to the coil packs, you must:
1. Identify the cylinders: Locate each spark plug on the engine. Usually, cylinder 1 is at the front of the engine, on the passenger side (right side in the US). The rest are numbered sequentially.
2. Use the firing order: Following the firing order (1-6-5-4-3-2), connect the spark plug wire from each cylinder to the corresponding coil pack terminal. Because the coil packs fire two cylinders each, there will be a 1-6 coil pack and a 5-4 coil pack and a 3-2 coil pack, which usually will be visibly labelled.
Crucially: The order on the coil pack itself is *not* the firing order. Each coil pack ignites two cylinders, and the coil pack doesn't inherently know which is the "first" of the two. You must use the firing order (1-6-5-4-3-2) to match cylinders to the correct coil pack terminals. You might find cylinder labels marked near the spark plug holes to be helpful.
Recommendation: Consult a repair manual specific to your 1999 Ford Windstar 3.8L. A diagram clearly showing the coil pack arrangement and spark plug wire routing will be invaluable to avoid misconnections. A miswired spark plug can lead to misfires, poor performance, and potential engine damage.
