Wet weather misfiring

ESCAPEE

MEMBER
2004 FORD ESCAPE
6 CYL
4WD
AUTOMATIC
95,500 MILES

My Escape has started chugging in rainy weather, and the check engine light will blink. When the weather dries up, it idles and runs beautifully, smooth and crisp. I have recently replaced all 6 spark plugs, and all the ignition coils look to be in good condition.
In older vehicles I have had, this problem of wet weather hesitation and misfiring was always solved by replacing the distributor cap and rotor.
What are the comparable components to a cap and rotor with my coil on plug system? Is it the ignition coil terminal, and could this be where the problem lies? Perhaps moisture is getting to it somehow.
Because it runs so well in dry weather, it doesn't seem there are any component failures, like plugs, wires, valves, etc.
Any expert advice is very much appreciated.

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

Yes. More than likely this is an issue with the coil. If you just visually inspected, it then you will not see the failure.

Clearly when it is wet you have a severe misfire that we need to get resolved because if the check engine light is flashing then that means it is damaging the converter.

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

The only issue with this is you have what is called coil on plug so that means you have a separate coil for each cylinder.

I am attaching the info below, but we need to start with checking the code to find out if this is one specific cylinder or something else.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Once we know what code is there, we can take the proper action, but I would suggest swapping the problem cylinder's coil with another one and then see if the misfire moves to that cylinder and that will confirm it is the coil.

I am attaching the info below on how to replace these coils. Please run through this and let us know what you find. Thanks

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