Top Issue- 02-05 Ford Thunderbird Ignition Coils COP

[autoprofessor]

Two questions on bad coils. 1) Is there a car code reader that can determine which cylinder is misfiring? My 20-year old code reader has been lost so I need a replacement. Hoping for a reasonable priced upgrade since the lost reader could not do this. (2) Despite being stored under cover and very lightly used since the last COP replacement about 5 years ago, the misfire condition has returned. I assume that it is the COPs again. Is there a good solution other than selling the car?

Best, Ken

The Blue Driver works for me just fine. I put NGK’s and cheap Rock Auto COP’s on when I first bought my 04 and have put 10k problem free.

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[queensbird]

Are the coils supposed to move when torqued to the valve cover? I noticed that the aftermarket coils someone put on the car move around slightly because the retaining bolt bottoms out before the coil clamps in place, is this the way the OEM coils are as well? I’m guessing not, otherwise there’s no reason for a torque value if you’re just bottoming out a bolt. I can fix this issue with a small washer placed between the bolt and coil if it shouldn’t be moving around.

 

[gregl32]

Are the coils supposed to move when torqued to the valve cover? I noticed that the aftermarket coils someone put on the car move around slightly because the retaining bolt bottoms out before the coil clamps in place, is this the way the OEM coils are as well? I’m guessing not, otherwise there’s no reason for a torque value if you’re just bottoming out a bolt. I can fix this issue with a small washer placed between the bolt and coil if it shouldn’t be moving around.

My OEM coils do have slight wiggle.

Two questions on bad coils. 1) Is there a car code reader that can determine which cylinder is misfiring? My 20-year old code reader has been lost so I need a replacement. Hoping for a reasonable priced upgrade since the lost reader could not do this. (2) Despite being stored under cover and very lightly used since the last COP replacement about 5 years ago, the misfire condition has returned. I assume that it is the COPs again. Is there a good solution other than selling the car?

Best, Ken

If it is the COPs you need to see if the sparkplug wells have any kind of liquid (oil, water, or ?) in them. If they do then you need to solve that issue first. I have 3 different devices, one is self contained. It's a Foxwell NT530. I also have 2 different dongles that hook up to my laptop. I have a couple different programs that can use the dongles. All of these can access all the different modules and read data, do testing and even do some programming. Way more functions than just reading check engine light codes including general live monitoring for misfires. Unfortunately, none of these programs show any live data options for monitoring individual cylinders for misfires. I have to wait until the specific cylinder misfires enough to at least set a pending code. The other choice is to disconnect the electrical plug from each coil one at a time and start the car and compare idle quality. You'll set another code about general ignition problem because it can sense when the electrical plug is not connected. It will not tell you which one is disconnected.

 

[TJJIM]

Well my '05 with 102,000 just started to miss every now and then and also when I give it the gas. I am thinking I have developed the COP problem so I plan on replacing the ignition coils this weekend and see if that resolves the issue. I do plan on going to Amazon and getting the coil set you indicated above as well as new NGK plugs plus some dielectric grease. Anything else I should do while I am under the hood? Any and all suggestions are appreciated. Thanks Mike

If there is oil at the bottom of the spark plug holes you need to replace the valve cover gaskets or the oil will ruin your new coils.

 

[jneuenburg]

Yes, start reading on post #1 if you really want to solve this issue. You could be treating the symptom and not the problem!

Click code reader or OBDII Reader for that.

Thread 'Top Issue- 02-05 Ford Thunderbird Ignition Coils COP'

Dec 22, 2016

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, 59.30 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!

Many people have had success with the coils above...

• tbird
• 2002 2003 2004 2005 coils condensation cops engine coils ford thunderbird
• Replies: 65
• Forum: 2002 - 2005 Retro Ford Thunderbird

• 

Yes read the whole thread.

My post #44 gives tips on tools and techniques. Get a 1/4" drve 7mm swivel socket like I showed.

A BlueDriver is an inexpensive plug in for the OBDII port and it displays things on your smart phone. It tells you which cylinder is misfiring.

 

[TJJIM]

My OEM coils do have slight wiggle.


If it is the COPs you need to see if the sparkplug wells have any kind of liquid (oil, water, or ?) in them. If they do then you need to solve that issue first. I have 3 different devices, one is self contained. It's a Foxwell NT530. I also have 2 different dongles that hook up to my laptop. I have a couple different programs that can use the dongles. All of these can access all the different modules and read data, do testing and even do some programming. Way more functions than just reading check engine light codes including general live monitoring for misfires. Unfortunately, none of these programs show any live data options for monitoring individual cylinders for misfires. I have to wait until the specific cylinder misfires enough to at least set a pending code. The other choice is to disconnect the electrical plug from each coil one at a time and start the car and compare idle quality. You'll set another code about general ignition problem because it can sense when the electrical plug is not connected. It will not tell you which one is disconnected.

Being a Ford Master Certified Tech for over 40 years, misfire detection sucks on these Birds. I had a hard misfire and used the Ford Factory IDS tool. I can look at misfire data live in a graph format. While it was misfiring the data never flinched indicating a misfire. So I tried my Snap-on Zeus with Ford software. Same test same results. It’s only from experience that I know what an ignition misfire feels like. Not like fuel related unless an injector is completely dead.
So I just replaced all 8 coils with Motorcraft and 8 new Motorcraft iridium plugs.