Top Issue- 02-05 Ford Thunderbird Ignition Coils COP

New guy here—I pick up my 2004 with 85,000 miles tomorrow. The Carfax for my car says the ignition coils were replaced at 53,000 and then an extended warranty repair on the ignition coil covers and wiper motor bracket seal was performed at 62,000. Does that fully address the COP problem? Should I be concerned about the spark plugs? No indication they have ever been replaced.
 
Hello, this will likely be the valve cover gaskets. They get less flexible with the extreme heat of the engine. There are o-rings around each of the spark plugs which will be the source of the leak. New valve cover gasket set is the only answer,not expensive but a bit of labour involved, particularly on the driver's side and involves the fuel line to be depressurized and split at the connection above the valve cover. Try Rock Auto where you have a choice of gasket brands. I've just done mine on both sides. Good opportunity to replace the o-ring at the base of the oil filler tube too. It's not a hard job, just a bit hard to get to some bolts. Good luck Ian
Are the Valve Cover Gaskets for the driver side and the passenger side the same gasket?
Thanks
 
My car started mis firing during a heavy rain. After a lot of labor i replaced the plugs and ignition coils. The car continued to mis fire. It had to be towed in. Garage said three of the eight ignition coils were bad. I had paid $44 for the set...Lesson learned. Car's good now. COPS.
 
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Since your engine started misfiring during a heavy rain and three coils were damaged, it would lead me to believe that either the Ignition Coil Cover/Wiper Motor Bracket Warranty Extension was never performed, or the new wiper motor bracket seal (5W4Z-54021A46-A) was never replaced.

doug7740
1955 Thunderbird Blue

Wiper Motor Seal.png
 
Has anyone had a problem with the plastic connector plugs/clips that are used to plug into the coil packs?

I started changing out the coil packs and spark plugs on my 2005 Thunderbird yesterday. Started on the passenger side. Took the dusk cover off no problem. I saw that two coil packs had been replaced by someone else. Then I carefully (and gently) unplugged each plastic connector plug from each coil pack as I removed each of them. I then replaced the all four spark plugs successfully. As I started to install the new coil packs and went to plug in the connector plugs to each of the new coil packs, two of the long plastic clips from inside two of the connector plugs fell out all by themselves. I was very gentle in the removal of the plugs from the old coil packs knowing that someone had been there before. However, now I have two plugs that do not "click" into the new coil packs. The connector plugs fit correctly onto the new coil packs but have no mechanical way for the connector plugs to stay attached to the new coil packs.

Anyone else had this problem? Can the plastic connector plugs be acquired somewhere and spliced into the harness? Or will I have to replace the harness for the entire passenger side of the car?

Or is there some other mechanical way to secure the connector plugs from the harness to the coil packs?

Thanks in advance.
 
Has anyone had a problem with the plastic connector plugs/clips that are used to plug into the coil packs?

I started changing out the coil packs and spark plugs on my 2005 Thunderbird yesterday. Started on the passenger side. Took the dusk cover off no problem. I saw that two coil packs had been replaced by someone else. Then I carefully (and gently) unplugged each plastic connector plug from each coil pack as I removed each of them. I then replaced the all four spark plugs successfully. As I started to install the new coil packs and went to plug in the connector plugs to each of the new coil packs, two of the long plastic clips from inside two of the connector plugs fell out all by themselves. I was very gentle in the removal of the plugs from the old coil packs knowing that someone had been there before. However, now I have two plugs that do not "click" into the new coil packs. The connector plugs fit correctly onto the new coil packs but have no mechanical way for the connector plugs to stay attached to the new coil packs.

Anyone else had this problem? Can the plastic connector plugs be acquired somewhere and spliced into the harness? Or will I have to replace the harness for the entire passenger side of the car?

Or is there some other mechanical way to secure the connector plugs from the harness to the coil packs?

Thanks in advance.
Did you purchase these- https://amzn.to/3HH4Qew
 
Has anyone had a problem with the plastic connector plugs/clips that are used to plug into the coil packs?

Anyone else had this problem? Can the plastic connector plugs be acquired somewhere and spliced into the harness? Or will I have to replace the harness for the entire passenger side of the car?

Or is there some other mechanical way to secure the connector plugs from the harness to the coil packs?

Thanks in advance.

Bob,

You can purchase the electrical connectors from your local auto parts store like NAPA or Auto Zone.


You can also purchase a complete set of 8 connectors from one of the many sellers on eBay.


doug7740
1955 Thunderbird Blue
 
Pic 1 is the broken piece of plastic that came from inside of one of the push-on electrical connector (plug) from the cars' harness.
Pic 2 is the push-on electrical connector (plug) without the mechanical piece from the pic above.
Pic 3 is a undamaged push-on electrical connector (plug) with the mechanical piece still attached to it.

All I am really looking for is a way to secure the push-on electrical connector (plug) that is without the plastic piece to the COPS. The plug fits the COPS just fine. My fear is that the plug may vibrate off the COPS because the it is lacking the plastic piece internally to "lock" it into place.

Thanks again.
Bob,

You can purchase the electrical connectors from your local auto parts store like NAPA or Auto Zone.


You can also purchase a complete set of 8 connectors from one of the many sellers on eBay.


doug7740
1955 Thunderbird Blue
Thank you Doug, you are a good man. You gave just what I was looking for.
 

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Thanks for the quick reply. I took a new plug and it didn't fit any of my existing spark plug sockets, so being a Jaguar based engine I tried metric and found the 17mm fit and said OK. Trying again this morning though and the standard 5/8" socket fits the plug and the hole.
I just used a 5/8 plug socket and it worked fine. Metric would be 16mm. Mine was a decades old Craftsman, measured .881 inch OD. I never used it much and it still had most of an old manufacturer sticker on it. It grabbed a little in the hole so I scraped the sticker off.

Obviously a proper spark plug socket with the rubber insert to hold the plug is important in a deep hole.
 
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Thanks to the experts here for monitoring and answering all questions, especially biddle. I have a few comments and tips after installing four coils and 8 plugs in my 2003 yesterday. I think one problem I had has not been discussed on this thread. I also have a question. Some of this is about tools.

The job was easier than some say. Anybody who is familiar with tools and doing easy stuff on cars can do it but having certain tools helps a lot. Yes, a 1/4 drive ratchet with 7mm socket is mandatory and a 7mm combination wrench is good to have. Extensions as shown in the picture below are what I used. The tools at the bottom were for the coils and the ones above were for the plugs. Tbird coil job tools.jpgI used the handled driver but it wasn't necessary. Some bolts needed the ratchet to loosen. A small magnet like on that screwdriver is nice to have. The circled tools are the 7mm sockets I used. The one on the extension is a swivel socket. It occupies LESS SPACE than a universal joint adaptor with socket and is REALLY HANDY for getting to those lower rear cover bolts, and for a couple of the coil bolts. I DID NOT REMOVE OR LOOSEN ANY PARTS TO GET ACCESS TO THE BOLTS ON EITHER SIDE. This is the benefit of using the right tools. I did not need to move a big wiring harness out of the way to get to the lower passenger side bolt. I could work the extension with swivel socket behind it, and unlike a universal joint adaptor and socket which flops around, mine could be pre-set at the proper angle and guided the last inch or two to the bolt. For reinstallation of that one I used a long mechanics flex-shaft magnet. Worked it behind the harness with left hand pulling harness away from the metal with my right, then put the bolt head on the magnet, guided the magnet and bolt to its target. Once in the hole the magnet can be pushed to the side and withdrawn. Then come back with the extension and swivel socket. Easy peasy. Another installation trick could have been magnetizing the extension and socket to hold the bolt. But the bolt can be inserted by hand if one is patient. By the way on my engine the lower driver side bolt is shorter than the others and works fine.

Standard sockets are a little quicker and more stable than the flexible types when no clearance problems. I found using the short and long extensions at different times worked well, and even joined together a couple times. I did not use a deep 7mm socket.
Here is the Tekton SHD08107 swivel socket. Well made and I like how it stays at whatever angle you put it:

Tbird 7mm swivel socket.jpg Some of the folks talked about carrying a spare set of coils in their trunk. Only a couple mentioned having the tools! Important! This little bugger will be included in my trunk tool set, as will dielectric grease. Maybe a spare bolt or two.

I thought a previous mechanic had stripped a cover bolt or it's fitting. A middle one. It turned but didn't come out. I couldn't pull it out with pliers. So I removed all other bolts so the cover could be flexed up at the front using a lever. Fingers might have worked, its plastic. This put upward pressure on the bolt so it came out. Turned out the steel female fitting came out with it! It had come unglued, maybe it stripped while over-tightening. It happened on two other fittings. Here you can see a fitting above the coil, and the cover shows a fitting that came off with the cover and bolt.

Tbird coil job cover bolt insert pulled out.jpg Tbird coil job cover bolt insert.jpg Note the fitting is knurled where it sits in the plastic manifold. These are glued or molded in during manufacture. So I needed to re-glue it. It and the bolt were stuck to the cover, so I put the knurled part in a vice and unscrewed the bolt. Then noticed the fitting has two expansion/ contraction slots.

Tbird coil job expanding cover bolt insert.jpg

Obviously I wanted to make the thing bigger so it was a press fit back into the manifold. So I put in a vice and tapped with chisel and hammer to open the slots wider. Then I glued them in. I used a two-part thread repair product on one, and blue Loctite on the other two. After curing, all bolts took installation torque. Next time I will use epoxy or Crazy Glue. Anyway we'll see what works long term. Moral of story is don't tighten the bolts too much.

I did the driver side because my mechanic's scanner said #5 was misfiring. I had all 8 coils on the shelf since reading this thread a year ago. I replaced all four on that side and when looking at the spark plugs I noticed a gap of .046. I was told gap should be .041. I have heard a big gap is hard on coils and this was 20% too big, So I put new Iridiums in it and decided to replace the other four plugs, thinking if they are worn that could hurt those coils. I don't know. I didn't replace those coils because I am curious how they last, and will keep a set with tools in the trunk for when travelling. The passenger side is a little quicker to do because fewer tool changes due to parts in the way.

BTW in 2021 I had purchased the recommended (here) ENA DG515 DG509. These are about 1/8" longer than the Ford ones that came out. So like the aftermarket ones you all talked about many years ago. Cover seated perfectly. Do the 2003 and later covers offer more clearance than 2002 or are these upgraded covers? I am going to buy another set and it looks like the latest and greatest is now the DG515 G-8 from AD Auto Parts via Amazon. The picture shows a connector the same as Ford. Shorter. Hope they work!

John
 
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Start by checking the fault codes and freeze frame data in the Engine Control Module to see why the warning light is on.

doug7740
1955 Thunderbird Blue
 
We bought our '05 last November with 54k miles on it. My wife has managed to put 3,000 miles on it since. No idea whether it has had the COP or spark plug replacement.

I took it out on the highway and, when leaving a traffic light, stood on it to see what it would do. It hesitated for what seemed more than a second, then the engine kicked in and it took off. I tried again several times while rolling at different speeds, always with the same result: The car staggered and then took off.

COP's?
 
Yes you should definitely do the coil packs and plugs. Also, make sure that you are putting 91+ octane gas. Then try again and get back to us...
 
Yes, I figured that would be best route, so the parts are sitting in my Amazon cart. We've never put anything but premium in it. And one bottle of SeaFoam when we first got it.
 
A dirty air filter will cause a hesitation too. If you really want to lay down some rubber you have to turn off the traction control and give it a little gas while your foot is still on the brake.
 
I have a few questions. There are so many knowledgeable folks on here, that I hope can point me in the right direction. My car has approximately 48,000 miles. I'm the original owner so I had some of the coil packs replaced under Fords extended warranty. I replaced more as needed, for a total of 7. The past few times I took the car out I noticed the same rubble sound like a misfire when I had issues with the coil packs. It's not on every start. Today it was on the 3rd time I started it when i was out doing a few errands. When I give the car gas, nothing no power. I restart the car and depress the gas pedal still nothing but within 6-12 seconds the car is reving. I have not checked for any codes as of yet. I have always had my car serviced and do not know how to repair it. I've read on here the coil packs parts are very inexpensive but to get a shop to do them it was about a $250 charge each time. So I ask you experts, should I replace all the coil packs if I get a code that indicates one is misfiring?
Also, I have read so many post about FEM going bad and pray that isn't my issue. I do recall reading a recent post saying a tell tail sign of a bad FEM is the light going out in the gear shift. Mine has done that. I thought it was just a burnt out light bulb. Since I don't have the ability to repair this car I often consider selling it before I get to the point of very expensive repairs and impossible to find parts. I love driving my bird and it has a very sentimental meaning for me so I always talk myself out if it.
Thanks in advance for any guidance.
 
I have a few questions. There are so many knowledgeable folks on here, that I hope can point me in the right direction.
Also, I have read so many post about FEM going bad and pray that isn't my issue. I do recall reading a recent post saying a tell tail sign of a bad FEM is the light going out in the gear shift. Mine has done that. I thought it was just a burnt out light bulb. Since I don't have the ability to repair this car I often consider selling it before I get to the point of very expensive repairs and impossible to find parts. I love driving my bird and it has a very sentimental meaning for me so I always talk myself out if it.
Thanks in advance for any guidance.
Everything you need to know has already been discussed many times in this thread about the COPS. Read post #1 which talks about how to resolve the COPS issue with less chance of reoccurance- /threads/top-issue-02-05-ford-thunderbird-ignition-coils-cop.5040
All cars can have a leaky valve cover gasket that fouls out the spark plugs, COPS etc, so replacing spark plugs without fixing the root problem results in a repeat problem.

Regarding the FEM, again read the FEM thread- https://forums.fordthunderbirdforum...d-front-electronic-module-fem-2002-2005.5560/

Much knowledge and wisdom are gained from reading. There is a plethora of information here already on both topics.
 
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