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My engine started sputtering and the EPC light came on yesterday. Went to my dealer and was told my engine coil is bad and I should replace all of them, which I did. Today I got a warranty extension letter in the mail re: manifold and fuel injectors being "faulty" and being fixed for free up to 120,000 miles. I have 38,000 on my 2012 Eos 2.0. Could the coils going bad be related to a faulty manifold and/or fuel injector? Just wondering.
 

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I only ever had one case of coils on a gas car failing. A coil although designed for the high votages should be reliable as it is a passive device.

In this car the coils were mounted directly over the exhaust manifold. I could see hairline cracks in the outer potting compound. My conclusion on this particular coil was the coil operating temperature plus its raised temperature being over the hot exhaust manifold had caused premature failure.

I have the diesel EOS, but look at yours and see if exhaust manifold heat could be a possibility. The solution is to design a heat shield deflector that fits between the coil pack and the exhaust manifold, or re-locate the coil pack if they are not the individual type directly mounted on the plugs. Search the general VW forums for other reports.
 

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Hi, I just purchased a 2009 VW Eos, and the dealer THOUGHT it was a bad coil causing the check engine light to go on, so they replaced one and tested it for a while, seemed solid, but then after delivery it bucked on me during highway braking and CE flashed, so back to dealer it goes. This time they took it to a VW dealer (I purchased from a Nissan) and they are taking care of the bill, BUT the VW dealers can hook the cars up to their fancy computers and see what's going on with all the coils and also what's on memory on the onboard computer -- they saw a random misfire, which generally means it's not the coils, so then they dug deeper and opened up the engine to find a bunch of carbon buildup, so now my car is getting de-carbed and new fuel injector seals; if that doesn't clear the issue my original dealership will also approve the other items on the list: cruise switch and longitudinal switch replacements. If someone can tell me what a cruise switch has to do with the engine/drivetrain, that would be great. This has been a crash course in how cars work for me, since buying this car, since before that I only leased new vehicles.

I'm writing this here so that you know, also you said dealership and not VW dealership so just making sure it is a VW one; the tech said with these cars they do need decarbing because of the turbo engine, typically at 80K but if the driver is real punchy on the gas and acceleration then sooner is possible. My car is at 57K. Also if you have been putting reg gas in instead of premium carb build up would happen sooner.

So, that's been my story so far. At least by the time I really take delivery my engine will be squeaky clean :)
 

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I’ve 3 fail so far. I have a 2007 VR6 with only 33k miles on it. The first one went at 30k or so. I ran the codes myself and diagnosed it, then replaced the bad coil along with all the plugs.
Recently, one of the original coils literally broke off halfway up.
22538


22539

I had to drive a screw into the soft part to pull it out.had
22537

When I bought the replacement for that one, I bought a pack of six so I could carry spares in my trunk.
Thank goodness I did that because I had another one go out only a week or two later.
Maybe it’s me, but I think there’s an underlying problem🙄. Now I see talk about a recall that I didn’t know existed. I’ll be checking that out.
Any other suggestions in the meantime?
 

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I think I already said it in reply #2.

It's not something you can easily fix, it's how they designed it for the operating temperatures and duty in the engine bay. Unless they can extend the coil body outside the cover and put some fins on it, I can't see a good recall solution. You could have a good look at their top cover to see if they have ducted air into it over the engine top from behind the fans and it looks effective? My Tdi cover has sound deadening foam underneath, but then I don't have your coils. You could also check if your engine fans run on for a minute or two after stopping with a hot engine in Summer. On newer V.Ws post 2012 they added a small electric auxiliary circulation pump and changed code in the ECU to purge the engine bay of hot air at key off if temperatures were too high. If you have the time, it would be informative to fasten a 'K' temperature probe to the coil bodies to measure their maximum temperatures.

When you look at where they mount surrounded by the engine cover, there could be insufficient free air cooling around the coil body, cooking it in the highest part of the engine where heat has risen and become trapped. I suspect if you removed the plastic cover and tolerated the poor aesthetics, you would have fewer failures? V.W could have manufactured the engine and life tested it in their engine labs, then the cosmetic plastics designers came along and added the covers afterwards!

They did a similar bad thing with the electronic exhaust pressure sensor - fixed it right over the hot exhaust manifold at the rear. With a few more inches of silicone tube there were plenty of alternative cooler places to fix it.
 
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