2010 ptt with 100k km. Got a coil fault and decided it was due to change all of the coils and plugs anyway.
Huge thanks to the makers of the step by step guide. You can wing it, but it makes life easier with the guide.
The job itself isnt that bad. 4 and 8 were not fun but not that bad to swap.
I did find some disturbing things though. I bought the car used last year. Got the full service history from Porsche, but to when I bought it. Early in its life the coils and plugs were replaced under warranty. Service line was replace coils and plugs. When I dug into things I discovered 3 of the coil bolts were snapped flush with the engine (4, 8 and 1). They just put the covers back on and hid it! I understand its a ***** to get at but come on! Also noticed when changing that only 1 of the coils had been replaced, the rest were stock. Nice on the service dept writing it up as all changed. A couple of other added bonuses. The plastic clip holding the drivers side wiring harness was busted, and discovered the passenger side torque support had one bolt with no nut and the other loose. My guess is they didnt replace the bolts or messed up the torque.
Plus side, sure enough cylinder 4 coil had a crack. Now just waiting on a right angle drill attachment so I can try to reverse drill the coil studs.

 

got to love top notch work at premium prices

 

I am new to Porsche, and am a bit amazed by these coil failures due to "cracking" and thus current leakage. I am 80 year old Geezer; and have never had such a coil failure in 65 years of driving domestic and imported cars, including Lucas coils.
Have done a bit of research onto the BERU site. BERU is owned by Beck Arnley or vice versa and is a major oem supplier. BERU has a pub "All About Ignition Coils". At page 21 under "Reasons for Replacement": "BERU ignition cooils are designed to last a car's entire life cycle. Notwithstanding this, there is always a need for replacements in practice. Usually this is not due to the ignition coils themselves but to problems in adjacent components or improper installation / removal."
Nowhere in this publication are references to coil failures due to "cracking."
I think the mounting bolt for the coils causes the coils to be held too tightly in expansion stressing the coils and even causing the bolts to snap.
Porsche uses common components whenever possible. With the flat six motors the coils were horizontal, and perhaps needed the extra fastener.
All OEM replacement coils, even made by BERU, have a provision for this bolt hole. On the Panamera the coils are somewhat recessed and shielded on three sides. On other cars the coils "stand proud". Perhaps this shielding causes to much heat expansion.
BERU makes "aftermarket coils" of its own design under part numbers ZSE 032 and ZSE 042. These "Red Top" coils have no bolt holes. Note, there are many Asian imitations of these Red Top coils.
My Panamera has but 24K miles and no sign of coil failures. But to further my theory, I have removed four of the six mounting bolts just to see if this makes a difference. Without the mounting bolts the coils have remained in place so far - 1000 mi. I did find that the OEM coils without the bolts are firmly held in place. In fact, it takes a bit of effort to break them out of their hole.

 

Interesting Kirkman. I was actually thinking the opposite. #4 had the crack and was one of of the locations with a broken stud.

Had the studs broken due to stress (or anything else, the cover mounting screw would still be attached (with the coil bolt head on the other side). So I don't think they broke after installation.

My thinking was, that not being bolted to the block would allow more vibration and movement, and might have caused the crack. But of course it could have been so many other things. Coils had been replaced a while ago, and if the dealer had broken the studs and not replaced then I put a bunch of time on it without them being bolted.

For sure the coils won't just pop out or work loose, they have a pretty good seal.

You'll know when the coil goes. You get pretty much every warning light come on, and it runs like you're on one cylinder. I found cycling the ignition would resolve. Luckily I was able to capture the fault one time and figure out it was a poopy coil.

I've found with previous cars that use stick coils, when one goes, the rest always seem to follow suit. I figured if I had everything apart, might as well swap them all. I've kept them as spares. I'm leaving one in the car incase I ever had another failure and I'm far from home.