As I write this, my Targa 4 (which is for sale) has 95,xxx miles on it. I think it's one of the highest mile 997.2's on this forum at least.

I purchased it with 82k miles last April, and quickly put those additional miles on her. Its been dead nuts reliable, and I even dyno'd the old girl thinking those miles and potential carbon build up may have robbed some power (even though it didn't feel like it).

The dyno read 277hp at the wheels. For comparison, a 997.1 4S with less miles , and several modifications including an exhaust and some software put down 284hp at the wheels , right before my car went on the dyno.

I've been very impressed at how this motor has held out with the mileage and how strong it still pulls. While no engine is perfect, the .2 motors (at least in my experience) seem to be largely trouble free and easy to maintain.

Time will tell as a larger sample set of owners get their cars into the 100k mileage territory .

 

I'm glad to read stories like this. I second your opinion of the 997.2 reliability.

 

It doesn't make any sense to compare dyno runs between different cars to evaluate engine performance. Way too many variables at stake! Those figures don't have any real meaning.

Can I ask why are you selling the car?

 

I agree with your comments here. Anyone who has a business specializing in servicing Porsches, and comes here to "market" fear mongering nonsense like this on an information forum, is just trying to stir up trouble without providing the proof positive to back up his innuendo:

"My last 5 years have been spent researching and developing the 9a1 engines, both DI and port injected. With these I am not making the same mistakes that I made with the M96/97 engines, and sharing what I've learned online. People don't want to hear the truth, they just want to believe that its all Unicorns and rainbows in the mechanical workings within their engines. Most of them don't even believe problems can occur when their own engine snaps a timing chain and blows it through the cam cover; they certainly won't believe anything thats written."

 

His point was that as cars age and as mileage gets up there, there is potential for power loss. Comparing 997.2 base car vs. a tuned 997.1 s model car is a relevant comparison, if the latter has many fewer miles, and some (potentially performance enhancing) mods.

Base 997.2 is 345 hp and 997.1 s is 355 hp. His post is just saying the dyno showed that his car is at, or better than, the expected relative output vs. the other car, despite being up there in mileage.

 

I make a control system for industrial machinery. There are over 40,000 of these in operation. Some have been in service for over 30 years. We get a couple of these a week to repair (we are the clearing house for virtually all repairs). So for every 40,000 weeks of machine operation (many at 24/7) there are two failures. One per 20,000 weeks. Or an MTBF (mean time between failure) of 400 years. This is statistically meaningless since none of these systems will be operating in 400 years.

But one of the biggest problems I have when I hire and train a new person is getting them to believe there is any reliability at all. They see a couple units a week fail and assume the product is trash.

It can be very hard to see the forest for the trees, even with numerical data in your face.

In the case of Porsche failures we have very little data to make any kind of a judgement. And I don't believe any of us (anyone, period?) is in a position to know failure rates or how to convert this to a rough term like reliability. We have trouble even knowing how many cars are in operation. And a lot of these cars get very little use. How many annual miles do Porsches in total see? How are they driven? How are they maintained?

I'm a relative newbie here, but from what I can tell, Jake feels he has been burned by his sharing in the past. This is a problem for all of us. Jake is a resource. We can choose to nurture that, or lose it. If we can revive Jake's participation (hopefully) then we all must realize that his views represent the trees in his part of the forest. But we all gain something from that view. We can accept those views or not, but we do have a responsibility to respect him as we respect everyone else here. I figure that what most of us know would barely fill a thimble next to Jake's bucket. I'd like to share that bucket.

Jake, I hear you are already booked for the whole of 2015. That's an amazing business model! Care to give us another chance? I own a 997.2. It seems that most of the reliability talk here is on the first generation. I would love to hear some reasoned thoughts including support for the newer cars. What should I be worrying about? Listening for? Maintaining against? Inspecting for? I suspect you can answer those questions. I'd love to hear back from you.

 

Well said. I've done business with him and he is an outstanding individual. His work is meticulously precise. I am over 600 miles away and some of the components that we agreed to replace in the contract, after tested and found to be functionally fine, were not replaced and I received a refund. How many mechanics would do the same? - yes I trust Jake.

 

You make some excellent points and I too would want Jake to be part of our community of knowledge sharing. Yet I think Jake needs to make sure he calibrates his views with the same level of thoughtfulness that he does with his excellent work.

I drive a 997.1 and try not to think that it will blow up every time I take it out and drive it as it was meant to be driven. If we worry about .01% failure rate, it does sour the ownership experience. BTW, are there any real stats as to what is the failure rate by MY of production?

Often we see those who identify a problem without ideas of how to prevent or minimize. I would very much appreciate Jake's view of what we can do to minimize failure rates other than the obvious frequent oil changes.

I hope Jake knows that his contributions are valued and can be of even greater value if positioned differently.

And for all the 997.2 worried owners, just buy yourself a good set of chisels when you need to chip away at the carbon buildup.

 

I'm not sure how accurate this is but I remember reading in Excellence last month in the Q&A section one of the authors citing these numbers:

1% for the first version of the IMBS - 1999 to 2001 or so
8% for the 2nd version (2001/2 to 2005)
1% for 2006 +

Perhaps someone has the issue and can check.

 

I would think so. All cars have some form of Air/Oil Separator. On my BMW they're called CCVs or crank case ventilation (and are also failure prone). Perhaps the 997.2 AOS is a reliable unit or too soon for failures to show up yet.

 

Except that you can't use a dyno to reach that conclusion. At most, a dyno is useful for comparing relative output of different engine modds on the SAME car providing you can match all other dyno runs conditions.

 

Of course they have. The thing is, when the AOS goes bad one doesn't see exhaust smoke only from one side's tail pipes...

 

Can you explain this to me (seriously). Why can you not reach that conclusion? Back-to-back runs on the same machine, measuring power output at the wheels?

Also, the result is what one might expect. This lends credence to the fact that these are comparable approaches.

 

Because the dyno behavior is different for 2 and 4 wheel drive cars. Because the transmission losses are different from car to car. Because the simple fact of varying the tension with which the car is hold steady on the dyno leads to different dyno results and so on...

 

Based on this you can throw the whole dyno deal out the window.