996 C4S Warning light and running rough

[Steve996]

Hi my 4S engine warning light just came on on the way home from work (in heavy rain), it also started running rough and significantly down on power. Temp and pressures are normal and no smoke etc.

Anyone got experience of a coil pack failure/bad connection? If so, were your symptoms as I describe?

I've had the car for just under a year with no problems and it has previously had a full engine overhaul about 15K ago a few months prior to my purchase with steel liners etc being fitted so I had presumed it to be a strong engine with most of the weaknesses sorted, it was also boroscoped priot to my purchase and was in good order (as you'd expect as it has only done a couple of K since overhaul).

It's now dropped off to my local garage for diagnostics but they will likely be a couple of days before they can give me any info so as ever I thought I'd open myself up to the speculative insights of PH!

[Trev450]

The fact that this happened in heavy rain does point towards coil packs.

[Roberty]

Yeah I'd go with a failed Coil pack.

Best of luck.

[Gmund]

Sounds like a coil pack has gone to me. I had one go, and it was exactly as you describe. The outer cases start to break down and crack, then it's just a matter of time. I had all 6 replaced by an OPC for about £600 if I remember rightly. Not cheap, but I was relieved at the time after a sleepless night worrying about all the horror stories!!!

[Steve996]

Cheers folks, here's hoping!

[DanoS4]

Coilpacks imho.

FWIW, they're about £100, and don't take long to change yourself.

Did mine in the drive with a jack and a socket set.

[Steve996]

Still not heard back from the garage, they did say they might not be able to fit it in today. If it is coilpack I'll probs just let them do it.......struggling for spare time at the moment....! I did the packs on a Cayenne S I had a few years back but they seemed a bit more accessible!

[Steve996]

Yep - it was cylinder 3 coil pack.......all fixed and back on the road....phew

[spyderman8]

Gmund said:

I had all 6 replaced by an OPC for about £600 if I remember rightly. Not cheap...

No st! From EuroCarParts they're currently £33 each.

[Pope]

spyderman8 said:

No st! From EuroCarParts they're currently £33 each.

Porsche have recently superceded the coils to a more robust design - resistant to corrosion and bigger/better performance - they are slightly more expensive but will last longer.