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Top Issue- 02-05 Ford Thunderbird Ignition Coils COP

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 had a similar experience doing errands. I stop for 5 to 15 minutes and when I start it up it idles very rough, but stepping on the gas and letting engine rev a bit (in park) it always seems to clear itself up. Electrical problems with the coils might be the problem but it seemed to me like a vapor lock or fuel injector situation. When I turn the car off maybe there is too much fuel in the cylinders when I go to start it, or one of the fuel injectors has fouled. Doesn't hurt to put a gas additive in the gas tank designed to clean the injectors. This would be my first and easiest step, which I am going to do after writing this!!. Do two tank fulls. But If this is happening very regularly under conditions like I describe and not reliably self correcting itself, risking you getting stuck, then I would do something more. Intermittent problems are not easy to solve cause if you take it somewhere and it isn't doing it no one can be of much help unless it threw a code. And yes if you get a code that one is misfiring and you haven't recently changed the coils, I would change them ALL out. The work to get access to any of them from what I have seen is substantial so changing one seems not worth the access effort. Or, at least change them all on the same side of the faulty one. Not sure about your FEM /light bulb problem is a valid thing to worry, but I just don't know, so I would Fughettaboutit.

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Hi all, my wife got a 2005 Thunderbird last summer, 37K miles. We have driven it 2k the last 12 months, and this spring, the check engine light came on, and the code indicated cylinder 7 was not firing the way it should. I figured it was the coil, so I replaced all four on passenger side with new plugs, and when I took the cover off on the driver's side, I noticed a good amount of condensation around the coils, and it must've been there for months. It was water, not antifreeze, no oil. Somebody told me that there is a leak around the windshield wiper motor. Can anybody expand on that? Does it only happen when the car is outside in rain? Or should I be looking at something else to find out how the condensation got in there? Any help is greatly appreciated.
 
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!

UPDATE April 2020
Here is the link for the updated part as of 04/2020 that fits better with the valve cover- https://amzn.to/31CezPd previously everyone was ordering parts galaxy which works, but is a tight fit.

There is a post below with installation instructions- https://forums.fordthunderbirdforum...hunderbird-ignition-coils-cop.5040/post-35040

Important- You may also have a problem with your cowl seal, wiper seal or valve cover gasket, which is causing the coils to fail! You can read more about that in this post. If you have coils problems after a few days/weeks/months it's likely not the coil, but an additional problem.


What you need to buy
1- Ignition Coils (Amazon Purchase Link)
2- 8 Spark Plugs (Amazon Purchase Link)
3- Dielectric grease (Amazon Purchase Link)
4- Valve Cover Gasket (Amazon Purchase Link) (EBay Purchase Link) (optional but highly recommended while doing the job)
5- If you need the deep & shallow 7mm sockets, here is a pack with both (Amazon Purchase Link) Also, this 1/4" swivel socket will help you get to the one hard to reach. Note: 1/4" drive makes the job easier!
6- This type 7mm wrench will make the job easier



View attachment 10794

View attachment 673
There are several other issues that cause the coils to short out. One is the poor seal on the drivers side of the wind shield. Water seeps under the seal on top of the aluminun wind shield motor and on to the valve cover. The neck on the valve cover is held in place with a rubber seal. Oil also seeps out around the filler neck over a period of time. The long narrow plastic covers over the coils also flex from heat and the oil seeps in. If you clean the surfaces along the top and both ends of the cover with a cleaner that leaves no residue. Alcohol will work. Then apply a thin beed along the top edge and the front and back edges of the covers this will prevent the oil and water from seeping in. The covers have no gaskets they relay on several layers of thin plastic to keep the oil and water out.
Go Figure.
 
After you remove the cowl cover the washer hose can be disconnected at the washer fluid hose connector.

doug7740
1955 Thunderbird Blue
Cowl Cover.jpg
Washer Hose.jpg
 
Car has 29k miles and is immaculate. Just developed an intermittent skip but only under load, it runs smooth as silk at idle. I ran the gas down and put in new gas, but no help. The check engine light is NOT on but I scanned it anyway and no codes show up. Wouldn't bad coils or bad plugs throw a code? I hate to start throwing parts like coils and plugs at it without some confidence. Would a plugged cat converter be something to look at, wouldn't that throw a code?
Thanks for any ideas
 
Car has 29k miles and is immaculate.
The car is also 21 years old, 2+ decades old.

The check engine light is NOT on but I scanned it anyway and no codes show up. Wouldn't bad coils or bad plugs throw a code?
Not necessarily, especially during early stages.

I hate to start throwing parts like coils and plugs at it without some confidence.
Pull the spark plugs and examine them. Since the COPS are a common problem as well as a leaking gasket, take a look at one and consider changing these items as maintenance as well- https://forums.fordthunderbirdforum...2-05-ford-thunderbird-ignition-coils-cop.5040 Nobody over the internet is going to be able to tell you for sure.
 
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#1 was dry. #2 was damp. #3 was wet. #4 was dry and didn't look bad. It doesn't seem to be oil but has a smell I can't place. If it is antifreeze, it doesn't smell like any I've smelled before.

IMG_20240327_164404.jpg
 
#1 was dry. #2 was damp. #3 was wet. #4 was dry and didn't look bad. It doesn't seem to be oil but has a smell I can't place. If it is antifreeze, it doesn't smell like any I've smelled before.

View attachment 31048
I am relatively new here, but the orange staining is indicative of water under that cover that led to rust, correct? I have seen other posts that looked similar. The fact that they are dry or wet when you inspected them, but all are "orange", would indicate that you have had water under the coil cover at some point in the past. I assume the water eventually evaporated (due to heat) but left behind the rust discoloration. Also water under the coil cover on either side of the engine would ultimately expose all four coils on that side of the engine to moisture once this area gets hot and the water turns to vapor.
 
I found a 7mm combination wrench at Home Depot for less than $6, but some of the lower screws were still difficult to reach. The driver's side front lower is almost entirely blocked by the tranny dipstick tube. I tried every combination of socket, universal, flexible shaft, etc. and eventually got it out. I just found this on Amazon- https://www.amazon.com/dp/B09BTTCW3Q?tag=thunderbirdforum-20
1712170349114.png
 
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2003 26000 after purchasing 5 weeks ago, driving through a strong thunderstorm that night, stopped for fuel, filling with 87 octane, service light came on when I started up. Wasted a week thinking it was fuel. Checking the diagnostic codes with an oil change, local shop wanted 1500 to 2000 to replace coils. After reading your posts, decided to take on the job. For practice I started on the passenger side. As reported the rear lower bolt was the worst. New plugs and coils from Amazon. Was going well until I tried to put coil cover back on, Coils were too high. Not wanting to use a liquid gasket, to make up the gap. Looking at my old coils found they were the original DG529. To replace, get ready to pay a lot more. After installing, the left side only replaced, Service light gone. Did replace cabin filter & wiper seal gasket while waiting to get parts.
Previous post asking about the wiper fluid tube, gently twist the loosened cowl up, to get to both. I had enough tube length, without disconnecting. I attacked the moisture intrusion issue. No signs of oil.
 
2003 26000 after purchasing 5 weeks ago, driving through a strong thunderstorm that night, stopped for fuel, filling with 87 octane, service light came on when I started up.
From what you posted, I agree that the ignition coils were the cause of the service light illumination. I’m also glad that you are going to purchase the proper coils for the car and not use liquid gasket to make up the gap in the coil covers. Since you purchased your Thunderbird 5 weeks ago you might not be aware that you are putting the wrong octane fuel in your car. As per page 170 of your owner’s manual, your vehicle is designed to use premium unleaded fuel with a minimum octane rating of 91 or higher.

Fuel.jpg
Being a dealer technician for over forty years I can’t tell you how many times I have seen vehicles with drivability issues, and in worse cases, engine damage because the customer decided to use a cheaper fuel.

Higher octane fuels are required or recommended for engines that use a higher compression ratio. Increasing pressure in the cylinder allows an engine to extract more mechanical energy from a given air/fuel mixture, but requires higher octane fuel to keep the mixture from pre-detonating or knocking. In these engines, high octane fuel will improve performance and fuel economy. Using a lower octane fuel than required can cause the engine to run poorly and can damage the engine and emissions control system over time. Many newer vehicles can adjust the spark timing to reduce knock, but engine power and fuel economy will still suffer.

doug7740
1955 Thunderbird Blue
 
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, but if you are looking for a brand name check out the Denson and NGK Coils. Click here to buy them on eBay.
View attachment 24204View attachment 24205

UPDATE April 2020
Here is the link for the updated part as of 04/2020 that fits better with the valve cover- https://amzn.to/31CezPd previously everyone was ordering parts galaxy which works, but is a tight fit. You can also get NGK and Denso name-brand ignition coils here.

There is a post below with installation instructions- https://forums.fordthunderbirdforum...hunderbird-ignition-coils-cop.5040/post-35040

Important- You may also have a problem with your cowl seal, wiper seal or valve cover gasket, which is causing the coils to fail! You can read more about that in this post. If you have coils problems after a few days/weeks/months it's likely not the coil, but an additional problem.


What you need to buy
1- Ignition Coils (Amazon Purchase Link)
2- 8 Spark Plugs (Amazon Purchase Link)
3- Dielectric grease (Amazon Purchase Link)
4- Valve Cover Gasket (Amazon Purchase Link) (EBay Purchase Link) (optional but highly recommended while doing the job)
5- If you need the deep & shallow 7mm sockets, here is a pack with both (Amazon Purchase Link) Also, this 1/4" swivel socket will help you get to the one hard to reach. Note: 1/4" drive makes the job easier! Some owners have reported this tool is also good for reaching the back one- https://www.amazon.com/dp/B09BTTCW3Q?tag=thunderbirdforum-20
6- This type 7mm wrench will make the job easier



View attachment 10794

View attachment 673
I just replaced my valve covers ,no big deal ,took a while ! , but I would like to tune up the designer of the engine compartment !
 
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, but if you are looking for a brand name check out the Denson and NGK Coils. Click here to buy them on eBay.
View attachment 24204View attachment 24205

UPDATE April 2020
Here is the link for the updated part as of 04/2020 that fits better with the valve cover- https://amzn.to/31CezPd previously everyone was ordering parts galaxy which works, but is a tight fit. You can also get NGK and Denso name-brand ignition coils here.

There is a post below with installation instructions- https://forums.fordthunderbirdforum...hunderbird-ignition-coils-cop.5040/post-35040

Important- You may also have a problem with your cowl seal, wiper seal or valve cover gasket, which is causing the coils to fail! You can read more about that in this post. If you have coils problems after a few days/weeks/months it's likely not the coil, but an additional problem.


What you need to buy
1- Ignition Coils (Amazon Purchase Link)
2- 8 Spark Plugs (Amazon Purchase Link)
3- Dielectric grease (Amazon Purchase Link)
4- Valve Cover Gasket (Amazon Purchase Link) (EBay Purchase Link) (optional but highly recommended while doing the job)
5- If you need the deep & shallow 7mm sockets, here is a pack with both (Amazon Purchase Link) Also, this 1/4" swivel socket will help you get to the one hard to reach. Note: 1/4" drive makes the job easier! Some owners have reported this tool is also good for reaching the back one- https://www.amazon.com/dp/B09BTTCW3Q?tag=thunderbirdforum-20
6- This type 7mm wrench will make the job easier



View attachment 10794

View attachment 673
I noticed the price for ngk & denso are significantly higher than the deal in 2016. Are the ena coils just as good for 42.00? Do the ngk plugs need to be gapped? Ed
 
I'm considering buying a t'bird 02 thru 05 not sure on what year but this problem I have been reading about coil packs going bad because of oil or water leaks is concerning, how often do they need to be replaced? If from an oil leak from valve covers and the valve cover gaskets are replaced how long before they leak and short out again? Can this repair be done in my garage?
 
I have been reading about coil packs going bad because of oil or water leaks is concerning,
Why would this be concerning? All cars, especially 20+ year old ones, with a valve cover can have a valve cover gasket leak that fouls out spark plugs, COPS etc. The problem is simple: when people replace the spark plugs and COPS on any car that has a valve cover and a leaking gasket, the problem reoccurs. What is bizarre, for some reason over the years, people with Thunderbird have decided to blame the car. LOL

Start reading on Post #1 if you want to learn about this topic- https://forums.fordthunderbirdforum...-05-ford-thunderbird-ignition-coils-cop.5040/
 
Why would this be concerning? All cars, especially 20+ year old ones, with a valve cover can have a valve cover gasket leak that fouls out spark plugs, COPS etc. The problem is simple: when people replace the spark plugs and COPS on any car that has a valve cover and a leaking gasket, the problem reoccurs. What is bizarre, for some reason over the years, people with Thunderbird have decided to blame the car. LOL

Start reading on Post #1 if you want to learn about this topic- https://forums.fordthunderbirdforum...-05-ford-thunderbird-ignition-coils-cop.5040/
It seems to be an engineering problem more than a car problem, I have also heard of this happening well under 20 thousand miles that happened on many cars still under warranty, I didn't expect such a protective answer, I was considering selling my 1998 RT/10 that is 26 years old with 28,292 miles and never had a valve cover oil leak for something a little easier to drive, now I need to re-evaluate.
 
The COPs and plugs should last much longer. They should not drown out. It is an engine or gasket design problem or a gasket material problem or both. I am not talking about an engine that has had its covers off for another reason and there was an installation error. But it is what it is, UNLESS it is a gasket material problem which could be solved by a manufacturer.
 
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