CT03911

Car hit 18k miles and I did the spark plug change.
All six plugs were surprisingly loose. It was not like I could turn them off by hand but the plugs were not on very tight. I guess I would add the coil pack screws were loose too.
I am glad I checked. I recommend you at least check the front plugs even if you are not going to change them all out. All six of mine were the same torque, so if you found your front ones barely tight, I'd say a safe bet they all need attention.
On a lift I did not need to pull either a wheel or the mufflers. I did have a fair number of tools available, multiple extentions etc.
FYI, the plugs looked pretty good, all six exactly the same with very minor gap differences and wear visable but do check to see if yours are tight at least.
The rear plugs were a pain. If you can get that back one out, the next two moving forward are obviously easier.
I imagine dropping the mufflers makes them all easy but of course I started with the front ones so when I got to the back ones I just worked harder. Next time I may drop the mufflers to help.

cfjan

Dennis, is it a hard job to change the plugs? I have bought the plugs awhile ago, and am thinking about changing them since the car now has about 25k miles.

I don't have a lift, just jack stands. What kind of special tools do I need? (You mentioned the extensions)

So one should really take the muffler off?

911SLOW

You need tool S9706 to use as a spark plug socket
add an extension 10cm tool FXW4
Use a ratchet / torgue wrench (20lbft torque on the plugs)
5 mm hex allen for the plug coils

It's quite easy with a lift haven't done it on stands..

joeycannoli

I will be doing a detailed DIY on this in the coming weeks as my GT3 is due for plugs

cfjan

That would be most helpful!! Thanks in advance!!

CT03911

You could always jack it and be mentally prepared to take the mufflers off if it becomes neccessary. On a jack I would think the wheel removal may help too.
If you have the plugs just make sure you get a spark plug socket that fits first before getting going. Don't use a regular deep socket, you will need the spark plug socket to pull the loose plug out and put it back in to be threaded without it dropping out of the socket.
Have a few different length extentions handy and I used a 5mm hex socket like this for the coil pack screws:
http://www.sears.com/shc/s/p_10153_1...&blockType=G12
There are two bolts that hold the spark plug cover in place over the plugs, the shield. Take it off.
Now you can see the three plugs on that side. Use the 5mm hex to loosen the two screws holding the coil pack. For the front two plugs you can probably pull the coil pack right off the plug and push it aside to access the spark plug.
For the back plug (with the muffler on) I could not do this.
If you have trouble getting the coil pack out of the way do not worry and do not force the issue.
Push the rubber boot up at the top of the coil pack and expose the attach point from the plug wire to the coil pack. A very simple clip is there. Lift it slightly and pull the clip assembly out.
Now the coil pack slides right out and the plug access is easy.
Three last points:
Make sure you put a dab of this http://www.sears.com/shc/s/search_10...lectric+grease into the coil pack head before putting it back on the spark plug.
Make sure you use a product like this http://auto.sears.com/automotivepart...2&blockType=G2 on the plug and coil pack threads before screwing them back in.
I tightened everything firmly but did not use a torque wrench. Mine are all too big.
Lastly, the plugs I put in were part # 999-170-195-90 from Porsche sourced by VIN number at the dealer ($12.77 ea list). They did not match the ones I took out and I seriously doubt the previous owner had them changed as I got the car with 4500 miles.
The old ones say FR6LDC. I think the new ones say FR6LDU but now I can not be sure. Interesting.
Hope this helps, sorry to be long.

enthusiast

Appreciate the information and I think this is the second post on loose spark plugs. 'Chuck Price' had one loose spark plug, see thread below

https://rennlist.com/forums/996-gt2-...highlight=plug


I also bought new plugs from a Porsche dealer using 999.170.195.90 and they are Beru ultra 14FR - 6LDU.

Porsche Parts Catalog lists 14FR 6LDU. I haven't changed plugs or checked them so I do not know what is currently installed in my GT3.

The maintenance book that comes with the 2004-2005 996 GT3 under Section I. Required for the Emission Control System, lists replacing spark plugs at 30,000 mile intervals. The GT3 marketing literature (dated 2003) stated every 24,000 miles or four years.


** Tightening Torques for M 96/97 Engine - GT3/GT3 RS **

ignition coil to cylinder head - 10 Nm (7.5 lb-ft)

new spark plug - 30 Nm (22 lb-ft)

used spark plug - 25 Nm (19 lb-ft)

KOAN

Good to remind people...

Dudley

Having an air-rachet available makes this task a lot easier and much quicker.
Otherwise, removing the coil pack screws and sparkplugs can be slow going whether the mufflers are in place or not.
My plugs were loose as well.

Serge944

If your plug is completely loose, you will here a very loud whistle as the plug vibrates in the threads.

I had two plugs with low tension and one that was pretty much finger tight immediately after I purchased my GT3 2 years ago. Interestingly enough, they were all on bank #2. At the time, my initial reaction was that the tech the previous owner used forgot to torque that bank...

Dan Jacobs

If your taking out the plugs changing the coils is a good idea. They're 8 years old and prone to failing at an inopportune time- like when you're at the track