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Misfire running rough after coil and plug change

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2004 e150 4.6l 219,000
New Motorcraft plugs and edelbrock coils

About 2,000 miles ago I changed plugs and coils. Now the van is running rough but no check engine light. Rough idle, sputters when accelerating. Sometimes certain rpms run fine.

Looking for advice and a vacuum diagram
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Do you have the firing order correct?
Good guess and the 4.6l is a COP design. The primary wiring is not long enough to reach other cylinders.

However do check that the conectors to the coils are fully engaged. Same with coils on top of the plugs.
The underside of the hood will have a sticker with an engine vacuum diagram.
If that is not sufficient, attached is a publication from Ford. Says electrical and that is how I would search. Has all vacuum routing as well.
I could not find a vacuum hose routing on the net.

With that kind of mileage, I would replace O2 sensors if that has not been done in the last 100,000 miles.


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i had the same problem after replacing the plugs in my 2017 f150, turns out one of the wires to one of the coil packs was not fully clicked on tight.
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