Cayman - mystery misfire....

[ianqv]

Dear members of the Parish,

I wonder if anyone has experienced the following....
Driving home this evening up the M20, had been purring along at 70 ish all the way to the Dartford crossing. As we slowed down the MIL light came on, along with "visit workshop" and we had a misfire!!
Oh bloody great!!
We tip-toed through the tunnel, pulled over in the services, key'd off and on again.
Mil light never cam back on, misfire much improved!!
On light throttle the misfire had almost gone. By the time we got home (30 miles later) the engine was running as sweet as a nut! no misfire, and no MIL light.
If I had to guess.... I'd say it felt electrical on the HT side of things.

Has anyone come across this before?

Many thanks in advance

Regards

Ian

[Cobnapint]

Sounds like a coil pack is on it's way out.

Don't drive to far with it misfiring - I did that many years ago with an M3 and fried the cats. Megga bill, long face.

[ianqv]

Cheers

Just read on a few on the U.S threads that coil packs suffers from cracks!!
Just looked on Design 911's website, £140 for a new set of 6 coils!!!

No doubt they are a pain in the arse to fit!!

Regards

Ian

[Cobnapint]

Sounds like a dealer jobby to me. I had one go on a 997.2 C4S under warranty - quite a common problem apparently.

German reliability eh..?

[gsewell]

Or could be some dodgy fuel.

[DRH986]

ianqv said:

Just read on a few on the U.S threads that coil packs suffers from cracks!!
Just looked on Design 911's website, £140 for a new set of 6 coils!!!

No doubt they are a pain in the arse to fit!!

The fault code should be stored even if the light is off and the car is running fine at the moment. The coil packs crack with age/mileage but are easy to inspect and change if necessary on a DIY basis. The price you've quoted sounds ok as I remember them being around that when I changed them on a Boxster about three years ago.