Top Issue- 02-05 Ford Thunderbird Ignition Coils COP

biddle

Forum Moderator
Staff member
I get a random short misfire sometimes. I think it is most likely a coil, but which one. I do not get a check light. Does anyone know how to find that culprit that is starting to go bad. I hate to replace all if I only have one that is bad
You get all 8 coils for less than 60 bucks----->https://amzn.to/2Rfp5Zd
Change them all while you are in there, and your spark plugs, so you don't have to keep doing it. Also, make sure your cowl seal isn't a problem or valve cover gasket. Read more about that in this post- https://forums.fordthunderbirdforum...ird-ignition-coils-cop.5040/page-5#post-38169
 
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2004 w/23k miles. Only had it about 5 months and have put a tad over 3k miles on it. Went to go on a lunch trip yesterday morning; she started fine (as usual), drove about 2 miles and noticed that the engine light had come on. I had reset it about a week after I bought it; code showed gas cap issue (replaced by previous owner 4k miles ago). About 125 miles into the drive, it started "missing" under a load (uphill climbs). Based on my research here, I'd already purchased a set of COPs and plugs when I first bought it. Before I start, I figured I'd see if there were any advice from folks here who had already done this job. Is there anything else I should replace while I'm already that deep into the plastic removal process? Appreciate any ideas and/or suggestions.
 
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/2RaLkj2 previously everyone was ordering parts galaxy which works, but is a tight fit. https://amzn.to/31CezPd

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. If you have coils problems after a few days/weeks/months it's likely not the coil, but an additional problem.

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If i may add a word of advice, i bought and installed this same set of COPs and Plugs in my 2004 and although it improved performance, i was still pulling a code that said "missfire cylinder 4". Turned out that the intake manifold gasket above cylinder 4 had failed and it was sucking air in right there. A good mechanic down the street sorted that out in 30 minutes, after i replaced the #4 cylinder sets twice. My advice is while you are in there replacing, check all around the seals to see if you see any premature wear. You may find a problem getting ready to happen.
 

JW in Dixie

Well-Known Member
If i may add a word of advice, i bought and installed this same set of COPs and Plugs in my 2004 and although it improved performance, i was still pulling a code that said "missfire cylinder 4". Turned out that the intake manifold gasket above cylinder 4 had failed and it was sucking air in right there. A good mechanic down the street sorted that out in 30 minutes, after i replaced the #4 cylinder sets twice. My advice is while you are in there replacing, check all around the seals to see if you see any premature wear. You may find a problem getting ready to happen.
One way to check for a leaky intake valve - spray WD-40 along the gasket while the engine is running. Sudden smoothness indicates where the leak is.
 

biddle

Forum Moderator
Staff member
Turned out that the intake manifold gasket above cylinder 4 had failed and it was sucking air in right there.
Yes, this is mentioned in post #1 you quoted as Valve Cover Gaskets -
 
Even these coils are higher than the stock Motorcrafts. Not as bad as some of the other aftermarkets coils but once the clips are installed on the coils there is still some interfearence with the coil covers. They will not seal completely and I did not torque them down all the way in fear of breaking off the screw ears. None of the sftermarkets are identical to stock but what can you expect for the price and being made in China. Should be O K as long as your Birds are not your every day driver including in rain storms
 

Mach5

2004 Merlot
No fear here. Engine suddenly started running badly, check engine light, code reader said coil "G" (number 7), driver's side. Armed with all the knowledge and info from our forum, I swapped out the coil pack in about 2 hours, cleared the code and went for a spirited test drive - and all is well again!

Forgot to mention! I noticed that the connector to the coil pack was loose. Whatever clip was supposed to be holding it on firmly was not engaging anymore. I fashioned together two zip ties, looped it around the coil and the clip and snugged it up and vahwala nice and tight. Checked and found the same problem on #8 and zip tied that one too. (Duct tape is for the weak - zip ties rule!)
 
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No fear here. Engine suddenly started running badly, check engine light, code reader said coil "G" (number 7), driver's side. Armed with all the knowledge and info from our forum, I swapped out the coil pack in about 2 hours, cleared the code and went for a spirited test drive - and all is well again!
I agree. This forum has been great since I got my 2003 Tbird last year. Especially this thread. Been a few weeks since I replaced the coils and plugs and she is running beautifully! Kind of surprised people are having problems with the cover. Maybe I was lucky. Hopefully everyone who replaces the coils enjoy their rides!
 
I want to thank the forum and the members for all the information on the cop problems and the document that explained how to replace them. My 2002 bird is original to my wife and I. It has been our go to summer car and have enjoyed it for 18 years. This year after it's winter sleep it started to miss and strain on hills. Since there are not a lot of mechanics that see these cars I went to the forum. Was I surprised for all the help. I would like to give a quick update on the progress and final result. I can do some car repairs and with that I felt with a little coaching I could fix the problem. The recent cops at Amazon were great as was the price. I purchase the plugs at the same time and dielectric grease. Following the process in one of the posts it took a Saturday of a few knuckles scraped and a little sore back but the job is done and the Bird runs wonderful. The new coils were a little taller but not much. Is was mostly the connector. If you are careful and follow the process of starting in the middle two screws and work to the outside several times the cover seats well. Thank you to tbird for the April 2020 update so I did not have the difficulty with the cover. Also, thank you to the forum again for all the helpful information.
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