Just replaced the plugs and wires on my wife's 97 AWD Aero and have a dilemma. The Chilton's manual I looked at shows a different spark plug wiring config for the 4.0 than exists in her van. I replaced one wire at a time pulling them through so they would route as the original wires did.Anyway the manual shows wires to the coil six pack in a mixed up order and in her van the coil six pack is wired from coil one to cylinder one and so on through coil six to cylinder 6.Does anyone have the definitive wiring diagram for a 97 4.0? Also I am assuming that the cylinders on the passenger side are one through three front to back and drivers side four thru seven.

 

One possibility for difference you see is that there can be two ways for the spark plugs to be wired. There are only 3 coils in the pack, and each coil drives two spark plugs simultaneously. They are fired together while the two cylinders are at opposite strokes, so when one cylinder fires for its normal power stroke (whatever BTDC), the other one is firing at the end of the exhaust stroke.

Take a look at the diagram and note the differences between it and what you see on your engine. If the differences are in the two cylinders firing from the same coil, you don't have to worry.

 

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