I have been helping a friend search for a 997TT and we found one that checks all of his boxes. The DME is as follows:The car was modified and maintained by a Porsche dealer. The exhaust is bbi but the flash is not clear at this moment; it was one of the known tuners (EVOMSit, Softronic, GIAC, etc.) though. I will be able to find out the flash author but just not tonight or tomorrow.

I vote the car is fine, but since I am not buying it for myself, I thought it would be wise to see if anyone had strong opinions one way or the other. Thanks, my friends!

 

It meets the limits I set for my purchase. (no more than 50 range 4) I do notice range 1 is fairly high... lots of rev limiter hits probably.

 

Looks like he's been hitting the RL a lot the last 80 hrs or so. I generally want to see at least a hundred normal operating hours after an episode like that to be sure nothing is broken, at least that's what pcna does when cpo'ing cars.

 

What are the limits for the ranges? Also how many hours now?

 

Thanks everyone. It sounds like nobody has serious reservations.

I agree. I was wondering if the flash raised the rev limits, resulting in more range 1 time. The owner said he has hit the rev limiter in 1st gear a fair number of times too though. That last range 1 hit almost certainly belongs to my buddy. Shoot, I must admit that 1st gear goes by very quickly, even when you expect it.

Good advice. Thanks. The range 4 hit was the one I was worrying about and that was 93 hours ago. Some of the range 1-3 hits are pretty recent; the owner did disclose that, on a supervised test drive, somebody hit the limiter a couple of times.

I just used my Durametric cable to get the DME info, so I am assuming standard ranges. 393.5 total hours now.

 

.....

 

Good thoughts. It seems like a well-cared for car with a seemingly honest owner who is an acquaintance of a colleague. It has been to the track and driven hard a few times but I don't suspect it has been abused. On the positive side, the car is near-local with the color and options my friend is looking for. Without compromising somewhere else or buying a car sight-unseen, this is probably the car for him. We will see how the price negotiation goes...

 

Well it depends on who you ask. Those who own a turbo and have driven the car for a while will say the report is okay, especially knowing that the car has a tune which typically raises the rev limited by ~500rpms. However given the choice we would all buy a car with zeros across the board.

I recently ran into this issue during my purchase however in discussing the issue with the owner I felt comfortable moving on the car that had a few overrevs.

 

most aftermarket flashes will raise the rev limiter to 7200rpms which is range 3. This DME read would not deter me. I'm pretty certain my car would read out similarly, and it is hardly abused

 

DME is fine IMO.

I've read more about people having issues with motors that were not driven hard enough (e.g. cylinder failures). I think overall maintenance is just as important.

I think more than a few stage 4s and any stage 5/6 would make you want to really look at the operating hours and make sure they happened a long time ago.

 

What kind of cylinder failures are you talking about exactly and how/why exactly did they happen etc??? This i would like to hear about.

 

It appeared to be more of a 996 thing. Just Google around, you'll find a number of articles.

 

Found this;

http://www.total911.com/news/996-eng...ou-be-worried/

But nothing on 997tt engines...

Interesting that the guy says in the third last paragraph how engines that had been flogged at the track have not been reported as having these issues but strangely doesn't allude to why that is. Perhaps he doesn't get to hear from everyone that has experienced failures so not sure if this info is flawed or this general thinking is based on the wider number of cars that don't do any or a lot of track work that he has been made aware of. Must be a reason for this....??

He does say that the failures appear to be due to the stress on the block from torsional twisting under high engine loads etc so if anything that condition applies to engines that are being worked too hard, not too soft....so it kind of conflicts with the general logic that babied engines are the ones failing. Then, If you read paragraph 11 where he quotes the liners cracking as a consequence of the blocks insufficient torsional rigidity when the engine is worked hard, it completely negates what he opines in the 3rd last paragraph when he says the opposite. Confusing stuff. Looks like that oversized salt shaker needs to come out here i.e. taken with a big grain of salt .

Interesting. Anyway i'll keep looking as and when time permits...

 

Still way too many ignitions in stage 1-3 especially for a car with only 12,000 miles

 

This is an article in which is one of many that I have written. This is on the 99MY Boxster engine issues yet it offers info from 2004 . Many articles and info are from ones that I have done. I also have ones on the 996/Boxster/Cayman etc intermediate shafts etc. I posted this so that while it does not affect the 997TT or 996TT it explains more about the post above. The 996TT and 997TT use separate liners of a different process and should not be confused with the 996,986,997 or 987 engine manufacturing process..


With the introduction of the Boxster, Porsche teamed up with Kolbenschmidt to manufacture their new water-cooled engine. These engines were to utilize the newly introduced Lokasil liners. The liners themselves offer a higher friction-free service area. This is most useful in regard to not only the longevity of the cylinder but the ever-growing higher mileage service interval. The cases experienced several issues starting with their porosity. In 1997 many of these newly released engines seeped oil through the cases themselves. This seepage was due to a problem in the manufacturing process. When the cases are made in a high-pressure die-casting, the air in the die has to escape. Should the alloy enter too fast and not let all the air out, trapped air pockets are the result. These pockets produce a porous area. This area would then allow seepage of the oil. The reason it was generally oil and not coolant leakage was due to the casting process. The air was trapped in the bottom to center rear of the castings, which housed the oil. Another well-known problem was the liner failures in late 1998 to early 1999. This would translate into only the 1999 model year do to production dates. These failures were also due to a manufacturing process. The cylinder liners are created from an alloy made abrasion resistant by adding silicon. Prior to casting the crankcase, the cylinder liners are fixed in position by an operator, then surrounded by a conventional aluminum alloy casting. This is done by inserting the pre-formed cylinder liners (manufactured by Plochingen-based Ceram Tec AG in a special freeze casting process) into the die. The dies are then closed and a high-pressure die casting (HPDC) and squeeze casting (SC) are utilized to achieve this. Three casting machines with a closing force of 1800 tons are used for this purpose. The advantage of the Lokasil process is that the silicon is applied only where it is needed. Lokasil base material costs less than Alusil and is easier to process. These liners or pre-forms are of high silicon content (20-27 percent) and offer a high reduction of friction. Kolbenschmidt holds the patent to Lokasil and is also known for their Alusil and Galnikal piston liners. Lokasil is a "sacrificial" bore liner comprised of silicon fibers in a binding that, when inserted into the block mold, burns out the fibers, leaving the high-content silicon surface directly in the bores. This actually allows the “sacrificial” liner to become one with the block thus eliminating a separate part in the block. In 1998 Kolbenschmidt’s casting machine was damaged. The time required to repair the machine could have slowed Boxster production down severely unless a fix was found. The solution was to reline some not-quite-perfect blocks that were on hand. Most of these blocks had a casting defect or a porosity problem in at least one cylinder. The fix was simple and absolutely acceptable to standards when done correctly. Kolbenschmidt began the process of the repairs until the casting machine was fixed. This process started by boring out the failed cylinder to allow for the insertion of the liner. There is also a groove cut around the top of the cylinder to keep the sleeve from dropping. This groove is approximately 2.0mm larger than the size of the cylinder’s width and goes down approximately 4.5mm. The next step was the insertion of these liners. It was decided to press the liners in the blocks. This is where the error occurred. Some of these liners were pressed in at a higher rate than the top retaining ring could handle. This would then fracture the ring at the top of the liner. When this ring failed under operating conditions, it was catastrophic. The ring itself would fall apart inside the combustion chamber. At this time the piston would force this debris up into the cylinder head. The piston rings would grab the liner and pull it down from the momentum of the crankshaft. Some of these engines were replaced from coolant loss before they totally self destructed in this fashion. This was due to the ring starting to come apart but not fully. This would compromise the sealing of the head gasket and cause the coolant to either be burnt or expelled from the combustion pressure. Porsche has not divulged exactly how many engines this actually occurred in other than a broad range of 2.5 engines in late 1998-early 1999. Nor have they released any engine numbers that have had sleeves installed. Generally speaking, the problem occurred within the first several thousand miles. They have been very good in correcting this for their customers in and out of warranty. Scott Slauson - PCA WebSite - 6/14/2004