Coils and Spark Plugs

I have a 2006 Boxster S with 46K miles and have not changed my plugs yet...I know I brought this up last year however I just couldn't do it...no issues, the P car is running great.

A fellow Porsche friend has a 2005 Boxster S with similar mileage and changed his plug to find out that all or some of the coils cracked due to heat stress according to the Dealer ..Should I expect to find the same condition??

MIKELLIG

The coil pack do crack due to heat cycling, and then they admit moisture. Sometimes its even very hard to see.

46k is pretty early, but it depends on your environment, how it is driven, and likely, luck.

Typically a bad coil will result in occasional misfire codes. Mine did. Since coils are anywhere from $40-80/ea depending, i would not necessarily throw a new set at the car yet. My 60-somethingk coils on my street car ( also several years of track use) are fine - i replaced my plugs at ~30k and inspected the coilpacks.

Damn, i'm coming up on that job again. Nasty without a lift.

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

Mike, I replaced the spark plugs on my 06 987 at 99K km = 62K mi. Spark plugs still looked in good condition. Car still had the original coils when I sold it.

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BLKBOXS
I have a 2006 Boxster S with 46K miles and have not changed my plugs yet...I know I brought this up last year however I just couldn't do it...no issues, the P car is running great.

A fellow Porsche friend has a 2005 Boxster S with similar mileage and changed his plug to find out that all or some of the coils cracked due to heat stress according to the Dealer ..Should I expect to find the same condition??

Coil deterioration is as much affected by climate as anything. I was reading about coil issues with UK cars way before I came across coil issues with USA cars.

If you have the plugs replaced the tech will check the coils. He should advise you if he finds any with signs of cracking.

I think it also depends on how you've driven those 6,000 miles per year, on average? Lots of short trips vs longer drives. Shorter trips can gunk up (sorry for the techno speak) the plugs with carbon. Longer trips can help burn off that build up.

so much more precisely fueled. The plugs used have the projected tip which helps keep the plug tip clean because under lower RPM/load usage the tip runs hotter. But at higher RPM/loads the incoming charge cools the tip to keep it from running too hot. The biggest problem is the electrodes just erode and the gap increases. Even with my 02 Boxster and its 4 ground electrodes they erode considerably as does the center electrode. It was eroded to about half its nominal diameter at one plug change. But the 6 tips were quite free of any carbon build up.

The other problem is combustion gases are forced into the (tiny) gap between the plug and head threads. You can see this when plugs are changed. The threads are discolored from the electrode end up sometimes over half way up the plug thread. This leaves corrosion forming compounds that can corrode the plug thread and the head thread. If the plug remains in service too long the head thread can get damaged when the plug is removed. This is why there is a change interval based on time.