F150 ignition coil in the rain

I drive a 2001 F-150 and I’ve had to replace ignition coils three times after a rain. It’s raining now, the truck’s running rough and I’m gonna have to do it again. I know this is an ongoing problem with Ford, my question is, is there a fix for it? Can I use some kind of rain guard over the hood vents? Would that be a waste of time and money? I’m not looking for something pretty, just practical. Thank’s much.

Is this engine the V6? If so have you replaced the spark plug wires? It appears the V8 has Coil On Plug ignition coils. Have you replaced the spark plugs recently?

Is the coil getting physically wet? Can you dry it and get it to work again? How are the coils failing?

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It’s a V8 and the spark plugs have indeed been reciently replaced. The coil gets wet when water finds its way under the hood or up from the wheel wells. How are they failing? That’s a good question. All I know is the engine’s missing and the mechanics always identify the water getting to the coil as the problem. Are you saying if I just dry out the coils the problem should correct itself? Apparently, this is a recurrant problem Ford is aware of but has no fix for.

You might replace the insulators. It’s a good idea to replace them when replacing the plugs.

Which engine? I think some of the engines this year use the COP and others use the coil pack so any answer may vary depending.

This is not necessarily a Ford engineering fault.

Have the plug wires been replaced?

The only ongoing problem with COPS, on Fords, and water is when people hose them down when they wash the engines. how many miles on this F150? Did you replace all he coils three times or have you replaced three coils? Did this start after the plug replacement. If so, that should tell you something.

Some people replace the boots when they replace the spark plugs at 100K. Like a lot of soft material under the hood (and behind the steering wheel), they can get old and decay Maybe most of your boots got torn when the plugs were replaced. Be sure to use dielectric grease in the boots when you replace boots or coils.

It appears I may have offended some of you. Let me assure you that I am not a hater or an attacker of Ford engineering in general and besides this issue, I love my truck. But I can also assure you that I am not making this up. This is a recuring problem in the F series, the E series and some other modle lines as well. Though no recalls have been ordered, Ford has informed their dealers of the issue and in the know Ford owners can get discounts on the repair. I say “in the know” because Ford has not informed owners. Spend some time on Ford owner posting boards and you’ll find complaints about this going back to the 1990’s. Rain water gets in around the windshield, the rear window and into the engine compartment. I did not hose down my engine and I certanly did not hose down my engine three times.

My truck is in the shop right now, recovering from last week’s rain and the weather’s supposed to get wet today. My original question goes back out… does anyone have a fix for preventing rain water from finding its way under the hood?

"The only ongoing problem with COPS, on Fords, and water is when people hose them down …"
Clearly, you haven’t heard of the Lincoln LS. There are multiple TSBs and the coil warranty was extended to 100K miles on several models. Oddly enough, one of the issues was water on the coils due to a bad gasket at the back of the hood.

I own a 2004 E-250 a 2008 F-150 and a 2002 F-150. Every one of them has had COPs replaced and each time it was after a RAINSTORM. The service manger at my local Ford dealer told me that every time there was a major rain storm that they had to replace the COPs on the F and E series V-8 engines. I have never sprayed a hose under the hoods of my trucks. The 2008 has only 10260 miles and it has been in twice for a coil replacement. Each time it was when I had driven through heavy rain. The E-250 and the 04 F-150 has been in for the same problems. My E-250 is strictly a work truck and I could care less if the engine is dirty.

An additional point I could make is that aged spark plugs could be the contributing factor, water under the hood or not.

A spark is going to take the shortest route to ground and on a known good, properly gapped spark plug any water under the hood may not make any difference at all.
Throw in subtle plug misfiring (which can occur with no codes or apparent symptoms) and the spark may choose to exit the plug boot rather than cross the plug gap.

It would be interesting (and near impossible to do) to compare coil failures against the mileage of the plugs in the engines which had problems as Ford, like others, has an annoying tendency to recommend leaving spark plugs in place for a 100k miles.

From here on, I will only respond to comments that actually address the issue I raised, not ones that attempt to deflect it.

The newer coils (make sure they sell you the newer part number, not the original one) are supposed to be less likely to fail. I would make sure that I put a lot of dielectric grease around the outer sealing lip of the boot, to try and keep the water from making it down into the well. (Of course, put some on the outside of the sparkplug insulator and some where the boot slides over the coil at the bottom.

Thank you.

I would just like to piggy back off the initial question. I have replaced all of the engine coils in my 2001 F-150 (King Ranch edition) twice maybe even three times. Why does this keep happening? Please only post solutions this has become very expensive for me.

I found that when I parked with the back of the truck up hill it was much worse with the water in the plug bores. This started on my 2000 5.4. Same on my 2007 5.4. Find it was partially plugged cowl drains. The cowl will full up enough to go through the anti spin slit foe the firewall ground strap. Water runs down the strap onto the engine. Obviously a mistake by the engineering department. Just seal the area around the strap with silicone sealer. I basically buried that end of the strap and bolt. Problem solved. FYI I never replaced a coil. Just dried everything out until I figured out the issue.

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