I have an old 2000 Ford Taurus that has been having some misfire issues. I replaced the wires and plugs about a year ago and hooray! it worked… until about a month ago when the check engine light came one. Misfire in cylinders 1 and 3… again. I ran some SeaFoam through and it did okay until this week, when the warning/flashing check engine light came back.
EDIT: Forgot to mention that it is idling very hard (expected) and feels like it is trying to stall, even before the misfire came back (also to be expected??).
So here is the question: is this a coil pack issue, or something more sinister (and expensive)?
Not sure which motor you have. Do not think it is the 3.8 which has headgasket issues. If it is the 3.0 vulcan motor, it is known for failing coil pack. Which is a $50 part and easy to change. You may have the OHC duratec motor which has individual coils per cyl.
A Common/ shared coil can fail with 1 cyl not firing. A motor with individual coils usually does not lose 2 or more coils together. It’s easy to ID the motor. Both the duratec and Vulcan are 3.0, not that it is a big deal
Still could be 2 bad coils. 2 cyls on same head misfiring is usually connected. Bad head gasket. Possibly worn valves. Did u try inspecting those plugs? U could move coil from a good cyl to the bad cyl and see if miss moves. Could be injectors.