Duc Hunter

I just did a tune from Markski and he recommended new coils and plugs. Makes sense. The coils are confusing me though. Pelican and others say the 997-602-104-04 are the right plugs and they are available everywhere, including Porsche. Porsche dealerships and online parts places like Sonnen and Gaudin say the 997-602-107-00 are the right coils. Searching for those in places like pelican not only comes up with “this part does not fit your car,” but in some places it comes up with “part not found.” So......which could is the right/current coil? Are their differences?

For those that will ask, Markski said get the Denso 3245 plugs gapped to .26 and call it a day.

993GT

99760210404 is the current part number for coils

99917019590 Porsche/ 7410 Bosch is the stock plug and works great,

another oem direct alternative is the newer 997 GT2RS plug 99917010390 / fr6dpp332 (8150)

Duc Hunter

Thanks for the quick reply. For plugs I will stick with Markski's recommendation since he did the tune. Posted that more for reference, since I am sure someone would ask.

Wonder why Porsche dealers are pulling up the current at the 99760210700 too.

993GT

99760210700 / beru zs177 are for m96 powered cars, boxster/Carrera etc
99760210404 /Beru zs178 is the Mezger/Gt1 coil for 996tt/GT2/3

Duc Hunter

Mic Drop!

993GT

..just stuff I get to deal with on the daily

2fcknfst

The Beck/Arnley part number (# 178-8425) with the 25mm bolts fits perfectly, no need to have an odd part/coil at the #5 cylinder.

Cheers,

pfbz

Beru Coils, $225 for six.
https://www.rmeuropean.com/Products/...404-MFG47.aspx

pancing

^ cheapest etail youll find new. Bosch plugs cheap too.

2fcknfst

That's a good price.

pfbz

^^^ They are a great place to do business with as well...

deadendd9009

I got mine from Rockauto. Google "ZS178 Rockauto", it'll prompt you to their website and run the search for you. They'll tell you they're out of stock, click on notify when available and they will order them for you. Took 2 days for them to get them in stock.

Coils came to about 30 bucks a pop, and they're Beru 997 coils with bolts even if they say they're Beck & Arnley. You can also get some Bosch 7410 plugs at the same time, they're 3$ each.

Cheapest I've found them!

T Kono

Speaking of coils, is the micro-cracking really that big of a problem? I just pulled my coils for the 60,000 mile service and 5 of the 6 have the cracks, BUT....the car runs just fine. Is current actually "leaking" out of the coils? If someone puts in new plugs and coils, how would you know the coils actually needed replacing? Any car will run better with new spark plugs. Also, the cracks I have seen are always on that "hump" area adjacent to the square top zone. The new, improved coils have that same exact hump, has anyone seen cracking on the new versions? BTW, this is not a money issue, I'm merely curious.........do the new taller coils provide stronger spark? If so, then I see the wisdom of upgrading, but if not then what exactly is wrong with staying with the originals? OK, back to work now.

pfbz

The micro-cracked coils seem to be susceptible to misfire in damp and rainy conditions... Since many Turbos hide from the rain like it would eat paint, some might never notice, but considering the comparatively low cost for coil replacement and the huge PITA to access them, seems silly no not replace cracked coils during a plug change.

I don't think the revised coils have any performance 'improvement' other than less prone to deterioration.

pancing

Nothing wrong with staying with original 996 part but yeah as pfbz says they act up with moisture. I read somewhere 997 beru plugs deliver more energy than bosch and over time they do deteriorate inside due to constant energy being fed through them. New ones still crack but less so. The older coil needed a pencil adapter to seat the plug, new one has them either built in or already attatched.So its really up to the car to tell you if the coils need replacing but do you want to wait till the car starts to stumble over itself?