acao

This weekend, I performed the 40k service on my 2006 997 3.6.
In the past, I performed the oil and filter changes every year. My annual pace also coincides with 10k miles per year.

This year's annual service was at 40k miles, so it was time to do the big list. Strangely, I didn't get a dash message at 40k miles.

This past year's mileage included 7 track days.

The oil change, oil filter change, engine filter change, and cabin filter change went without incident. The oil drain plug is starting to get rounded off, so I'll order a new one for next year.

I started out with 7 qts of oil, which resulted in a min level reading. I added the 8th and that resulted in a middle level reading. Perfect. This includes all the oil dumped out of the filter and housing. O'Reilley Auto had Mobil 1 0w-40 on sale for just under $5 a bottle.

While the engine filter box was out, I cleaned the throttle body and the mass air flow sensor. The throttle body had dirt, but wasn't dirty. The MAF looked very clean, but with electricals, it's not about what I can see. I think throttle body cleaning should be part of the minor maintenance routine.

I started on adjusting the parking brake, but once I got the panel off of the rear console storage area, I couldn't see the adjustment buckle. Because my parking brake takes 4 clicks to engage, 5 to lock, and 6 for an incline, I decided it wasn't worth taking out the whole console to find the adjustment buckle. Not for two clicks of improvement. I hate disassembling the interior. I'll never get used to the force required to disengage those clips, all the while trying to get it back together without damaging some plastic and introducing more squeaks and rattles.

Just when I was about to tackle my brake pads, I realized the bag containing my replacement pads actually contained my old pads (I keep those as spares). So much for that, maybe next weekend. The fronts have 5-6 mm left, the rears 4 mm each. Plenty to drive on through the summer, but not enough for a track day. My visual rule of thumb is to replace when the pads are as thin as the backing plate. I had new front pads this time last year, so 10k miles and 7 track days is pretty much it. At least double that for rears.

Original rotors are still good all around. One more set of pads for the front, and then the rotors will probably need to be replaced.

Then, I tackled the spark plugs. There's been some debate on this and other forums as to whether this should be done on at 4 years or 60k. I agree with the folks who go with mileage, years be damned. Plugs fire. That's it. It's not milk, age isn't a factor. But, I decided to replace the plugs anyway, because I wasn't certain what I'd find going in.

I came to the task with lots of study on this board and renntech. Good stuff and correct. No doubt about it, plugs are difficult, but only because accessing them is a bear (and other four letter words).

The passenger aft plug is the most difficult, then driver's aft, then on forward with the passenger side being more difficult than the driver's side. The mufflers had to come down. Unless you've got E.T. phone home fingers, I don't see how it can be done with the mufflers in place. Fortunately, dropping the mufflers is (relatively) easy. Five nuts drops each muffler (2 by the cats and 3 by the engine), and the trickiest part is rotating the darn thing to get it out. It's like Tetris, if I played Tetris in real life while simultaneously engaged in game of Twister. It would probably be easier to loosen the rear bumper, but unnecessary. I need to look into some elaborate ratchet extensions for next time. This time, I used a plug socket, one 3" extension, another 3" extension, and then the ratchet. Put each segment onto the plug in the engine, rather than putting the segments together and then trying to maneuver it onto the plug.

Because the information here and renntech was so good, I didn't encounter any surprises. The only surprise was my success.

At 40k miles, the plugs looked good. There were some deposits, but none on the firing tips or the electrodes. The electrodes still had lots of material. No signs of oil, bridging, or heat problems. If your engine is in order, the plugs can easily go to 60k miles. I don't have photos because my camera doesn't take good pictures that closely.

The coils looked good, except the driver's aft coil. That coil had superficial cracking. There's a drain pipe exiting right above the coil (uncharacteristically brain-dead design) that obviously did no favors to that coil. I didn't have new coils ready, so I moved the cracked one up front, and moved a nicer one aft. I also tried to move that drain hose. With the cracked coil up front, I can swap it out easily the next time I have that wheel off, without having to monkey around with the muffler. Otherwise, the coils should be able to go a long time.

The plug job alone took about 5 hours. 80/20 rule applies here: 20% of the work took 80% of the time, and 80% of the work took 20% of the time.

While we're under the car, I must say 3.8 owners got the short end of the stick when it comes to headers. The 3.6 headers are decent, especially compared to the pigeon feet on the 3.8. Never mind X51, I think strapping 3.6 headers to 3.8would be an improvement. 3.8 headers are obvious crippleware, designed to sell you the upgrade.

Here's my advice on the plugs:

• 60k miles should be fine unless you're misfiring.
• Be ready with 2-4 extra coils. They're pretty expensive, so I don't see the need to buy all six just in case. 2-4 should have you ready.
• There's no room for a torque wrench, so pay attention to the effort to loosen.
• Wear eye protection.
• Never look straight up at your work zone. You want nuts and sockets to fall on your chest, not in your mouth or on your tooth.
• Never move your head until you're clear of the undercarriage. The suspension knuckles leave welts.
• If your dealer charges $600 or less to change the plugs, that's not a bad price given the effort. I would seriously consider paying that. Fortunately, next time isn't for a while. I'd do it again, but I would definitely explore the world of specialized ratchet extensions. I'd also think hard about coordinating the spark plug work with some new exhaust parts ("While you're at it" is such an expensive phrase). A muffler with a smaller profile would be great. But, the reality is many owners won't reach 60k, and a great many more won't get through a 2nd plug change interval.

Once it was all buttoned up, things ran great. Possibly better. Definitely not worse. There's an improvement, I won't say it's earthshaking. Between the oil change, filter changes, cleaning of the MAF and throttle body, the plugs, and my sense of satisfaction, I can't isolate any one thing as the cause. Also, doing my services annually means my car never gets into a state of such disrepair that drastic improvements are noticeable. I consider that a good thing.

My car has always had a slight hesitation/stumble/dead spot in early throttle tip in while in 1st and 2nd, on a cold engine. There's less now (less severe and less frequent), but it's not gone. I was hoping.

I'm glad I did the work, I enjoyed it, raised my mechanical competence, and treated myself to foie gras, ribeye, and a St. Emilion that night.

Replacing plugs wasn't necessary at 40k, but neither was any of the rest absolutely necessary. Any improvement may be just as much perception as reality, but I do know the car is definitely not worse off.

It was about $150 in replacement parts and oil, so the savings were substantial if that's your motivation.

Dariof

Very nice report.

I called an authorized Porsche repair place out here and they charge $300.00 for the plugs.

After reading what you went through, I will pay that all day long.

I also change my engine and cabin filters, oil and oil filter.

I was going to tackle the brakes, but I am not sure I can do that. The Porsche repair place wants $675.00 for brakes and $120 for the brake fluid.

ADias

Excellent!

JW911

Awesome write up! Hats off to you on.

I'm very much a DIY'er but sounds like the plugs are worth the dealer investment. Brakes on the other hand are a no brainer. There are no special tools or contortion required and you don't need to be upside down.

helispud

GOOD JOB! It always feels good to do some of this maintenance yourself ... and the car does seem to run just a bit better after a DIY session. Plus you are now alerted to a possible coil problem down the road.

YA911Fan

Excellent writeup!

Just curious what kind of jackstands you used (and also how many) -- interested in the height and safety aspects. I'm assuming you don't have a lift...

sharmat

Had mine done recently for about $260. Thought it was well worth it considering what a PITA plug removal is. The plugs were going on 6 years.
As far as the time interval for spark plug change, the recommendation for 4 years is due to concern about the plugs being "frozen" to the heads. If that were to happen, it would be an expensive repair.

PHDX2

Great report---always helpful to get DIY accounts and insights!

REBor8

Really nice accounting of the task. And, yes, doing your own maintenance is satisfying!

wwilliams88

Very nice writeup! Thanks for Posting!

Clifton

Great post!!! I'm very much a do-it yourselfer and enjoy reading about other's trials and tribulations. I always mean to do write ups and take pics etc, but generally the DIY alone takes all the steam out of me.

Thank you for making time and sharing your findings and experience with the forum. Cheers!!!

acao

This is a legitimate concern. On a venn diagram, this would be where "Catastrophic," "Unlikely," and "Easy to prevent" overlap. I didn't see anything to be gained by waiting for 60k, except being lazy. Because I was already getting the car on jack stands, getting dirty, and the weather was nice, lazy wasn't persuasive (and I'm a lazy person).

acao

I don't have a lift. I used 4 jack stands I bought from Harbor Freight. They are rated 3000 lbs. My jack stands have a U-shaped saddle. I covered the saddle in Plasti-dip, and the jack points sit nicely in there. There are good jacking instructions on this board.

I have a jack from Harbor Freight too. I use a hockey puck in the saddle. It's not a racing jack, so I can't get it far enough under the car to lift on the preferred rear jacking points on the suspension mounting brace. The instructions here say use the suspension jacking points and place the stands at the sill points. Because my jack couldn't reach, I did the reverse. I used the sill jacking points to lift and placed the stands on the suspension jacking points. An old trick from when I had a Boxster. It doesn't come across well in words, but if you encounter the problem, you'll know. It's just weight, so the same point that can hold a jack can also hold a jack stand.

Jacking puts a prudent fear of God in me, so I only raise the car to the minimum useful height. That means my jack stands get to stay in their lowermost setting, which is still high enough to get the tires off the ground and for me to creep under.

Even when the car is on jack stands, I use backup. I leave the jack touching (but not bearing) a jackpoint near my work area. If the work involves taking wheels off, lay a wheel underneath the jackpoint so that if a jack stand fails, there's still the jack, and if that fails, the car can fall onto the wheel(s) instead of my head. I try to avoid risks that could result in closed casket.

If I need to go higher than that, I don't go to the higher jack stand setting directly. I basically get all 4 up on the lowest setting, and then work my way around raising the car in stages. It's probably unnecessary, but I feel better about minimizing chassis torsion, uneven loads, and lateral forces on the jack stands.

Edgy01

Excellent write up! I suspected that the mufflers and plumbing removal would help with access--thanks for the insight.

997_rich

Adding to this thread it- I just did the passenger side plugs. It took me about 2 hours just for the passenger side but it's the first time I've done this car and it was a bit tricky.

As mentioned above the muffler should come off. I was able to do it without removing the muffler but it took well too much longer than it should have. I also used every combination of 3/8" extension that I had (and I have a lot). I also had to use a flexi socket screwdriver with a torx bit to take the rearmost passenger side coil off. All of my coils were superficially cracked. I reused them all but I think I'll replace after another 20-30k miles as a proactive fix (but I didn't have them on hand this time).