Top Issue- 02-05 Ford Thunderbird Ignition Coils COP

Joined Forum this week. Coil failure can probably be cured by doing what expired Ford Program 07N09-S1 states regarding replacing the wiper motor bracket seal along with the coils and coil cover. Search the web for that program to get the part numbers for the seal and coil covers. Buy those parts from the Ford dealer and have any competent mechanic install the parts. Or do it yourself. Replacing the seal was the only thing I had someone else do.
Every time I took my 2003 T Bird to the carwash or drove in a heavy rain the coil failure occurred on the passenger side, because that seal leaked water onto the coil cover and the water got into one or more plug holes. The new seal and coil covers stopped the water contamination. Too bad I didn't find out about the "secret" program before it expired.
 
I went through my first COP job last week, and thought I would share some observations and pictures. I bought this ’04 base in the first week of January, and up until a few weeks ago it had run fine. I was familiar with the COP problems as I had owned two Lincoln LS years ago. In fact I joined this forum to find out how the COP problem was being addressed post-warranty, and found a lot of helpful advice here that encouraged my decision to purchase the car.

A few weeks ago I encountered some serious misfiring and flashing check engine light, so I ordered up the Parts Galaxy COPs and a new set of NGK plugs (7994). Several previous posts gave some helpful instructions, but they notably used the passenger side for demonstration. “Look how easy!” LOL All told, it took me about 90 minutes to replace the plugs and COPs on the passenger side. Might’ve gone quicker if I wasn’t doing laundry at the same time.

As others have noted, I found the new COPs have a higher profile, and as such the plastic cover would not fit back down squarely. The net difference in height appears to be about 1/8”. Here are the two side-by-side.

Difference in coil height.jpg

By alternately tightening the six cover screws a little at a time, the cover went back down fairly snug but I doubt it would be water-tight. I ended up pulling it off again and applying a bead of Permatex Black to improve the seal.

Here’s a tip a friend showed me. No rocket-science here, but he told me I would save time to tape the spark plug socket to the extension. Once the new plug is in place and tight, it’s really easy for the extension to separate and leave the socket stuck on the plug.

spark plug socket2.jpg
I also found something I had never seen before. A couple of the old plug tips were a bright, oxide red color. A little Google research showed the most common reason for this is the use of an octane booster or intake cleaner added to the gas. Guilty as charged.

spark plug red tip.jpg

With the passenger side done, I moved over to the port side. And this is where the fun began. Lots more stuff in the way there. Despite this, I was able to get five of the cover screws out with little difficulty. I had to move the power steering reservoir to the side slightly, and it was necessary to push the dipstick tube aside a little. Also removed the fuel vapor solenoid from the top of the strut, and disconnected the fuel line at the engine and pulled it back out of the way.

The bottom screw all the way back closest to the firewall was the challenge. I was able to get a socket on it, but it’s so close to the brake booster there was no way to get a ratchet on.

Back screw clearance.jpg

So I ended up using a 7mm ignition wrench to remove it, and it took about 20 minutes making small-increment turns. I couldn’t find a 7mm gear wrench.

With the cover finally loose I began to withdraw it. That’s when the nightmare appeared. As another poster mentioned, these covers can keep water out, but they can also serve to trap water in. There was enough water under that cover to start a koi pond.

condensation.jpg

The entire recessed area under the cover was rust-stained; water all down in the plug wells; and there was condensation all over the packs and wiring. This set of packs also looked different. These had no writing on top, where all of the ones on the passenger side had numbers and codes stamped on them. Probably replaced sometime in the past.

rusty inset coils out.jpg

rusty coils.jpg

The car was only out in the rain a couple times, and through the car wash a couple times. The wiper seal had been replaced previously, and I had seen no signs of leakage around it. When I bought the car the engine was extremely clean, so it’s possible it was pressure washed. Who knows where the water came from. I may replace the wiper seal again just the same.

So I went about a very methodical cleaning process. First, I used paper towels to sop out as much water as possible from the wells, and then allowed everything to air-dry for a day or so. I left the old plugs in to keep any debris from falling into the cylinders, and cleaned up as much of the rust coating as possible. All of the screw heads were rusted, which is probably where most of the color came from. I carefully treated all of the screws and bolt heads with an OSPHO-type cleaner to retard the rust.

Once the outer area was clean, I used compressed air to blow debris out of the wells. A shop vac was helpful too. The hexes on the plugs were heavily rusted, so when I began to remove the plugs I stopped every few turns and kept blowing out debris before finally removing the plugs and exposing the cylinder.

Next I applied some dielectric grease deep down in the wells and on the plug seats. Then came the new plugs, and the new coils. The coil wire connectors have a watertight seal, so there was no sign of moisture or corrosion in those connections.

Everything came back together well, and the engine is running smoothly again.

new coils and plugs in.jpg

The last part of the project was to get the coil cover back on. Like the passenger side I added a generous bead of Permatex Black around the entire perimeter of the cover, as well as the channel where the coil wires exit in the rear. While I have no illusions, hopefully this extra step will keep water out in the future.

Something else I observed: both of these coil covers had a date stamp inside of ’07. The TSB that covered this issue (TSB 05-16-2) provided new coil covers, so it would seem a prior owner took advantage of the TSB.

It may not always be possible, but if you’re considering buying one of these cars it would certainly be worthwhile to pop these covers off and have a look for any surprises. I don’t know if I would have walked away from this one had I discovered this mess before buying it, but it certainly would have affected my offering price.

I’m grateful for all the helpful hints and suggestions from previous posters, and hopefully my observations above will serve to help someone else along the way.
 
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As others have noted, I found the new COPs have a higher profile, and as such the plastic cover would not fit back down squarely. The net difference in height appears to be about 1/8”. Here are the two side-by-side.
View attachment 1866

To clarify, you used the Parts Galaxy COPs and they work, correct? Lots of people have ordered these and installed them without any issues despite the slight variance in size.
 
To clarify, you used the Parts Galaxy COPs and they work, correct? Lots of people have ordered these and installed them without any issues despite the slight variance in size.
These were the Parts Galaxy COPs as shown in the 1st picture. They are working fine. The only problem was the difficulty getting the covers back on--which "lots of people" have also reported experiencing.

For my money and time, it was worth using the Parts Galaxy COPs, even with the cover issue. I have greater confidence they won't leak after adding the Permatex seal to the covers. For the price, these coils are the way to go.
 
These were the Parts Galaxy COPs as shown in the 1st picture. They are working fine. The only problem was the difficulty getting the covers back on--which "lots of people" have also reported experiencing.
I was wondering about that because I've read so many reviews where people had a mechanic do it and they said they had no issues at all, or people with experience had no issues. Sounds like, at the end of the day, they do fit and the covers can go on. Great post, thanks for taking the time to do that.
 
May 24th, 2018. Check engine light came on. White exhaust smoke. Engine shake, obvious missing. Analyzer said it was No. 2 Coil misfiring. Took it to the Ford Dealer. After a day he called and said they want to replace all 8 coils becuase the gaskets failed and oil was all over the coils. I said, "how much?" They said $2600.00. I said "no way." I had them just replace the bad coil and wipe the oil off off the others and replace all gaskets. The ended up charging me $1400.00 So.............I ordered a set of coils from Amazon It runs great. If another coil goes bad I will replace them all myself.
 
May 24th, 2018. Check engine light came on. White exhaust smoke. Engine shake, obvious missing. Analyzer said it was No. 2 Coil misfiring. Took it to the Ford Dealer. After a day he called and said they want to replace all 8 coils becuase the gaskets failed and oil was all over the coils. I said, "how much?" They said $2600.00. I said "no way." I had them just replace the bad coil and wipe the oil off off the others and replace all gaskets. The ended up charging me $1400.00 So.............I ordered a set of coils from Amazon It runs great. If another coil goes bad I will replace them all myself.

I never let the Dealer replace any of my COPS. For what they charge for just one COP, one can get a full set of high performance COPS off of Ebay or Amazon (I have had the best success with the Red Dragon COPS). If you can't do them yourself, order a full set of plugs and COPs so you can find a good local mechanic to change them for you. My local mechanic hates me because when I pull up, he knows he is changing number 4 or number 8 or both. I do all the others myself. Another good investment is either a OBDII handheld or one of the new BlueTooth/WiFi dongles and get the App for your phone. That way you know which COP is bad and can just change that one.
 
After reading every single post on this thread, no one has addressed the problem. Why do they fail? Is it the wiper seal or the cowl foam seal, or do these coils just suffer from a bad Ford design?

.
There are two main reasons COPS fail early and four things that cause the two reasons. Water/moisture/condensation or Oil are the two reasons. Reason one, and it goes with oil, is a bad Valve Cover Gasket. If you have oil on your COPS this is why. IIRC this is a bigger issue with 2002 Tbirds then other year models, but just the same if you find oil on the boots it is a leaking Value Cover Gasket. Reason two, you or you detail guy power or steam cleaned the engine and now moisture and condensation have gotten under the COP boots. Extreme high energy being produced for ones spark plugs doesn't like oil, water, moisture, or condensation as it causes an arc to the grounded motor and kills the COP over time. Reason three, water/moisture getting under the cowl seal and then condensing on/under the COP boot. Replace the cowl seal. Reason four, water getting past the wiper seal, see Reason three. Replace the wiper motor seal.

I do NOT buy factory plugs or COPS.
 
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I replaced all 8 and new NGK plugs and new mass air sensor and still have the miss and doesn't throw a code. I have been to three different mechanics in the last month. Am at wit's end!
 
Mechanic thinks that the coils I got from Amazon are the problem. He is going to replace the #5 coil with a Borg Warner Coil.
Doesn't matter what he thinks. He's guessing at this point unless he pulled the plug out and examined it. Which Coils on Amazon did you buy? The ones from Parts Galaxy have a lifetime warranty, so send the one back you replace. Any part regardless of brand could be faulty. 200-300 people or more have bought these in the past year and you are the first that has reported a failure in the thread. There are 54 reviews on Amazon and one said it misfired after a week. Good luck, hopefully insight from myself and others will point you in the right direction.
 
A new set of COPs ride in my trunk, hopefully, like insurance, will never be needed.
 
2002-2005 Ford Thunderbird and Lincoln LS have a widely known issue with Ignition coils going bad and also fouling out spark plugs causing misfires
. Just by replacing these components you may be able to bring new life to your engine!

At the time of this post, 46.99 for an entire set of Ignition Coils! Can't beat that! If you have a 2002-2005 Ford Thunderbird I would buy these just to have on hand because of the history of these going bad! Don't forget to order 8 spark plugs too because the coils foul them out!

Here is the link http://amzn.to/2ilnIo3

There is a post here on how to replace or here.

Important- You may also have a problem with your cowl seal, wiper seal etc, which is causing the coils to fail! You can read more about that in this post.


View attachment 673
View attachment 1351

Bought these (and a spare set) and am very pleased !! Thanks for the recommendation !
 
In that the replacement FoMoCo (Motorcraft) coils (6) have not failed over a five year period, 'suggests that there may be justification for my using the Motorcraft DG 529 replacement coils.

Silver Bird

No justification at all, these have a lifetime warranty and are 46 bucks for all 8 coils! That's about how much one motorcraft coil costs. Why would you pay 8x as much? Motorcraft warranty is like 1 year. Numerous people have used these in the Lincoln LS and Thunderbird and had good luck unless they had other underlying issues causing the coils to fail.
 
Hello from Germany,
I replaced all 8 COPs on my 05 T Bird 2 years ago with Dragon Fire Coils and new NGK standard Spark Plugs,
3 weeks ago on the Highway during acceleration I lost power and rough engine behaviour,
code P0356, P2105, P1000, U0300...
I ordered straight away 8 new COPS (again Dragon Fire), during replacement I found #4 contaminated with corosion/steamed water, Ignitorplug coroded - replaced 8 Cops and #4 Sparkplug but no help,
it was #6 Sparkplug with no more gap between the electrodes....unbelievable....looks like it was bended together by mechanical force, after this Plug replacement nice smooth engine ops...so not always COPs, this time a 3$ part....20181109_215751-01.jpeg IMG-20181110-WA0002.jpg
regards from Germany , Rudi
 
My #6 COP went bad so I just installed a new one from the 8 that I bought in 2017 and have been riding in the trunk.
#6 is on the driver's side - more difficult than the right side due to one screw jammed under the power brake . Fortunately, the Ford house left that one out on the last visit there, so it was about a one-hour job, plus a few minutes to recover tools around the motor and under the car, of course. Recommend a mag pan. FYI, the coil location from driver's seat:
L -- R
5 -- 1
6 -- 2
7 -- 3
8 -- 4
 
Update:
Coils purchased above, installed tonight - The difference is remarkable. Beyond expectations. OEM original coils had 44K on them. I'm very pleased with the results and just hope they last awhile. Time will tell .......
 
Just joined and wished I knew about this option. I replaced all of mine last year myself, using FoMoCo parts and I spent 20x the amount listed on Amazon :mad: Curious how these hold up / compare to the Motorcrafts I put in...
p.s. If anyone is intimidated by the work, it's a real piece of cake. I didn't even have to replace the coil cover gaskets.
 
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