cvtbenhogan

What a tough job. That coil screw on the passenger side (rear upper) was an abosulete bitch. Getting boot cover back on was hard too. You need a small flat box ratchet that takes a 40 torx bit. I needed a long screw driver wedged on top to keep the box ratchet in place when starting the screw back on. See pic. Btw. Lot more soot in driver side exhaust which seems typical on these engines. I'd worry except #6 plug was dry as a bone and white grey, and there is minimal oil consumption.

Anyway no difference in idle, possibly a smidge smoother. Plugs came out easy after 10 year years and the old coil packs were in good nick so they went right back in. Plugs were probably good for another 50k but what is done is done.

Took cans and wheels off to leave room. The cans are heavy enough but easy to put back on. If I could do again I'd replace the muffler coupler bolts and screws and manifold bolts. Fairly rusty. Looking underneath you feel like putting on new stuff like headers and cans. The stock headers look awful. Maybe next time when I change out plugs.

4.5 hours of mild hell. Recommend doing a side a day and start with the hard side first (passenger side).

cvtbenhogan

Plugs passenger side and coil pack.

cvtbenhogan

Plug.

JW911

Glad to see some confirmation that these plugs come right out even after being in your cylinder heads for 10 years. For some reason Porsche thinks you need to pull them out every 4 years.

That one in the photo looks pretty sooty but the electrode surfaces seem hardly worn and probably still firing just fine.

I pulled mine after 6 years and 60,000 miles. Actually looked cleaner than that. They were firing just fine and I noticed no difference with new plugs. A lot of people pull their exhaust to make things easier. But it really is not necessary. I completed my job in about 3.5 hours. I suppose the extra time I took doing contortions and cleaning the blood off my knuckles was less than the time it would take R&R the exhaust.

Well kudos to you for taking this on yourself. It is a satisfying feeling for sure.

upier

Is yours a 997.1 or .2? I just did my .2 and it was easy. Pulling the mufflers was too easy to justify not doing. Hardest part was moving the heat shield out of the way. Wore nice mechanics gloves so I minimized the blood loss. I'll take a pic of my old plugs and post here. No soot on mine.

cerbomark

Here are my plugs after about 5 years and only 10/15K... Was worried about them not coming out easy because of time and Porsche recommendations. They came out pretty easy. Next time I d like to try without taking exhaust out. That took me as long as everything else. Dealer wanted $700!!

Bruce In Philly

That plug does not look healthy to me. I've done two plug changes at the recommended 40K miles and they look like they had a slight dusting of cinnamon on them.

Peace
Bruce in Philly

cvtbenhogan

My 997 is a dot 1. Maybe the super close up/lighting made the first spark plug pic look super sooty. Here is another pic a bit farther away. I'll check them again. Overall, I think plugs are not so much time dependent as they are mileage. BTW. I didn't remove the headers but thought about replacing the manifold bolts as a preventive measure, figuring they'll be coming off at some point should I get new headers.

Ahsai

Your coil(s) may still be ok for a while but if you blow up your pic above, you can see there are already cracks on the 3 and 7 o'clock positions within the middle rectangular area.

cvtbenhogan

Keen eye. I thought most packs were very lightly cracked and should go another 40k as I don't drive in the winter. I moved 1 plug with the most cracking up to the front drivers side in case it goes bad. Would be a quick change out.

I let the cheap devil beat the maintenance angel on this one. Will see.

Ptech1

Exactly. So all the hell you just described will have to happen again to replace the coils one at a time when the fail, or all at once as soon as one begins to arc/misfire.
I always recommend them to be replaced at the same time as plugs on almost all .1's at this point due to the saving of labor costs up front at the expense of buying new coils now. Maybe not the smartest move financially for my shop (could obviously make more doing it twice). But, honest advice keeps my customers coming back for the right reasons.

cvtbenhogan

Quick update.

After 500 or so miles I notice that the warm idle no longer wanders up and down. Now it's dead flat and steady at 800 RPM. Yes dead flat, I like that!!! Warm starts are improved as well. So I have a more positive view on the plug change.

Fined

good data points here. thanks O.P.

Macster

Plug changes are time dependent. You can see discoloration all the way up the plug from the tip. The discoloration comes from combustion gases being forced into the threads. These gases are corrosive.

One wants to change the plugs *before* the corrosion can have the head threads compromised.

As with other things in these engines the plugs are the sacrificial item in the plug/head partnership. I'm always puzzled that one would seek to extend the service life of a set of very inexpensive spark plugs at the risk of a very expensive cylinder head.

And as you noted the engine perked up so the plug change was not uncalled for even though the miles were low and one was willing to risk a longer change interval.

TT-911

10 years is not (too) long for a 'good weather' garage queen.