4 years ago I installed all new COP's in my 5.4L because two had gone out and I didn't want to get stuck some where. I figured I'd just replace all of them, the dealer even telling me they'd been updated several times since 98'. Last night, I was on a 70 mile drive, on the way back and going up a slight hill I started feeling a vibration that was more than just bad roads. Moments later a "flashing" CEL came on and kept flashing all the way home. I babied it back using lower gears to keep the revs up because it didn't have the power to get up hills in O-drive. I checked my onboard Edge Evolution and it said P0301 #1 cylinder misfire. It's only been about 40,000 + miles since I installed the new set of 6 after the two already replaced back in 2010. I figured they would last another 100,000 plus miles like the OE's did? Motorcraft DG508. They were supposed to have gotten better, not worse?

 

I always keep a spair under my seat. I bought a cheap ratchet/7mm socket and extension. It may be in the baggie under my seat for years unused or i might need it on the way home tonight after work. Who knows. one of those things

 

Coils are expendable parts the same as spark plugs, shocks, tires etc.
No way to predict failure except over long term trends and evaluation efforts.
The coils live a harsh life in their location with constant heating and cooling that expands and contracts the coil winding and the Bobbin it's wound on causing lead breaks at the terminals and shorted turns..
Being wound on a machine, the wire tension could have been too high at the terminal and pulled or broke off from work hardening expansion and contractions.
Bottom line is expect failure at any time with new or any age parts.
The Motorcraft coil is the standard for quality but not a guarantee of no failures.
These coils have been used by Ford from as far back as the mid 90s over the total number of cars and trucks produced, so the failure rate is low compared to the number that have been installed from the factory.
To design and produce a coil that would almost never fail would bring the cost of the coil too high, times 8 cylinders each engine, under production conditions..
I just lost a coil about 2 months ago getting on the thru-way with no warning but had a new spare for that occasion.
Good luck.

 

I have some of the old ones left over that I replaced. At the time only two had failed but with the high milage I decided to replace the rest of them and be done with it for a while. I did the coil test last night on the extra one I will temporarily replace with until I can go buy a new one or two to have an extra on hand as you guys explained. "Rock Auto" has Motorcraft DG508 for $41.99 cheapest around by $20.00 +. Uh, dam I just tested that one again and no secondary reading, and only 1.0 ohms on the primary two leads, so I'll have to buy a new one. Forgot to mention, I've had the exhaust leak (#4) on that bank as well now for the last 10,000 miles.

I guess I could look at the plug to to check it out, but its probably soaked from driving 70 miles with no spark, AP 103. Next time it'll be APP 103's. Hell, I'll probably have the 03' 5.4L in it by then with any luck, at least before winter.

 

Get this, I just replaced the #1 COP with a new DG508 and when I pulled the old one out, the inside of the boot was full of pure clear oil. I also replaced that spark plug AP103 anticipating trouble with it and it also had clear oil on the top. These coils must be oil filled? There's no other source of clear oil on the vehicle that could have caused this. I blew out the hole with compressed air first and saw no oil near the valve cover gasket. Engine oil was changed last fall with Mobile 1, 5W-30. That sure isn't clear right now. Ever seen this before?

New plug and COP, started right up and runs great so far. Test drive in a few minutes. I cleared code with Edge Evol. before starting work and did not remove battery connections to avoid relearn on test drive.

 

See how easy it is when just addressing a present condition and solving for it?
Last I knew there was no oils in these coils but you never know what advancement have been brought forth.
If indeed oil is part of the build, it presents still another issue as you fell into.
Last one I cut apart was dry. Just to see how it was made and why there are problems with them.
Look at the output area where the spring sets on the blade for a crack letting any oil drain out. Let us know.
Usually oils for that application are non conductive such as mineral oil but does not guarantee the oil will not break down in the presence of high voltages and heat plus the boot material getting into the act..
Good luck.

 

If it was only inside the boot I'd think maybe someone was too liberal with the dialectric grease.

 

It was not DE grease. It was clear oil that came out of the coil. I asked the dealer parts guy about how many times these coils have been updated since 98', he laughed and said many times.

Another thought I had is if there is a lot of copper windings in these coils wouldn't that make recycling them smart and even profitable. That's a lot of copper people are throwing away, a valuable albeit precious metal these days.

 

I stayed up the other night and read a post about an EXPY where the guy couldn't find out why his coils kept misfiring after doing all the tests, finally using Bars head gasket stop leak to solve a moister problem getting on the boots shorting them out fixing his problem for the next year until he could trade it in for a new F150.

That's why I posted the thread to see what else was out there in the way of problems to search for once I got into the project. We took it out tonight for a good 80 mile drive to burn any unburned fuel out of the cats and all is well, runs great and even picked up some added milage that bad coil has been stealing from me.

I'll tell you, I thank my lucky starts it was the #1 COP because the rest are a bear to get at! had it properly (BTB) fixed in less than an hour. I'll be ordering an extra one like I said from "RA" for $41.99 to have on hand in the truck for future COP failures on the road. I just saved myself a couple hundred bucks not going to the stealership. My Edge Evol. was a great help in watching the temp and reading and deleting codes. Now have the P1000 that will take some time to turn it self off once it's finished it's cycle. That Edge Evol. has paid for itself over and over again. Now I'll cross my fingers for a while.

 

$41 ? for one? WOW.. I bought all 8 for $60.. and i even gave one to my brother and one to a friend to toss under their seats. I know i bought cheap, I know they can fail. I can change any one in 5 minutes or less. So i by the cheap ones. They are so cheap i don't worry about it.. Fails, Pull it, Toss it. Pop in another cheap one. Good to go. untill tomorrow or never. Havn't had a failure in a year now.

 

You'll end up spending more money in the long run that way. $7.50 each, I find that hard to believe, very hard to believe, even for an off brand. What you must consider is how hard they are to get at when removing and installing them. You want the longest interval possible between changes, not to mention the extra wear and tear it puts on the connectors plus the waist of natural resources you encourage buy buying such low quality products and the loss in performance that you may or may not notice that is inevitable when it comes to Ford COP's. Motorcraft or not!

 

I was going through my service log last night to enter this new repair and found it interesting that that particular COP was diagnosed and replaced at the Ford dealership just after we bought it used in 05' and lasted 55,000 miles before failing, also 9 years of hot summers and cold winters adds an age factor. The dealer wanted $76.00 each + tax. I did well to find the best OE product locally in-stock for a negotiated $59.99, $6.50 less than they offered it to Joe public and installed that day. I wouldn't use anything but Motorcraft when it comes to coils.

 

No offence but i think you reading to much into it. They are so easy to put in. We are talking about COP's right? They are easy to change. 5 minute deal with one ratchet and step stool.

Bought 8 last last year when one of mine failed #4 (picture of History from ebay below $61)
A week later #1 failed so i swapped that out too. So i have two in the truck now. So far so good. 15,000 miles. Daily Driver. Thats pretty good mileage so far don't you think? Out of a $7.50 coil. Or rather $15.
One under the seat. My brother had one fail so i gave him two so he has a spare. And gave one to a friend for a spare. So i got what, two left in the box. Change one a year. Good for three more years. Or tomorrow.

Quick search on ebay found more $55 for 8 and warrentee? Havn't had one fail to worry about warrentee and probably shipping would cost more. Search ebay-> New Ignition Coil Coils ON PLUG PACK SET OF 8 For FORD LINCOLN MERCURY DG508

How many more miles and years you expecting to get out of your truck? They are so cheap, it is a non issue for me. it is a personal preference thing i guess.

 

If you want inferior parts in your truck, that's your business I guess. Experience tells me to always you high quality parts. Most everyone will agree with me on that. I do so and find the best price to boot. I don't go to the dollar store and buy mega packs of batteries that are worthless either. BTW, your link did not work.

 

I have bought a couple sets of coils off e-bay for $10 a piece. Original FORD ran about 150K and i started haveing 2-3 failures. Put in the $10. units and i loose about 1 per year. They are cheap and easy to install. Performance is the same.