Just to make the point that any posts we may be involved in that are connected to Gen 1 or 2 engine failures, reasons and fixes - are for those who have experienced failures. Posting information does neither make a failure more likely to occur but sometimes includes advice about what they should do to avoid it or delay it.

I agree that these engines are very comparatively reliable in the modern era and that running costs are reasonable (especially with reliable independent specialists) but there have been some adjustments or changes that can help engines last longer (like Gen 1 LTT, thicker oils and Gen 2 full warm up procedures). These came about from engineers analysing the reasons behind actual faults that had to deal with (not imaginary ones) and have benefitted owners Worldwide.


Furthermore those specialists with good reputations that repair engines and improve the outcome by eliminating or minimising known weaknesses - provide a good service to owners who - regardless of how reliable overall the cars may be - have never the less experienced an expensive failure and prefer an alternative to re-fitting the same engine that already experienced their failure for less cost.

Some (like us at Hartech in the UK) even include a monthly paid service plan (also covering free labour for most wear and tear faults) that enables owners to budget their costs and protect against a full cost engine failure rebuild - however rare or not that might be.

So while we can all agree on and praise the models and the general reliability performances let us not at the same time try and imply that they never go wrong nor that some form of scheme to minimise costs if they do - is not worth considering nor that the independent sector do not provide a superb alternative if and when they do.

Baz

 

 

 

Doug, I think you need to calm down and realise that nothing in my post will make a gen 2 9A1 go wrong and perhaps also recognise that we do not have to do exactly what you demand but are free to express our opinions whether or not you agree with them.

When the Gen 1 M96/7 engines stared going wrong there was the very same reaction trying to deny reality but gradually it became accepted that they had weak spots that could be repaired successfully.

The Gen 2 9A1 is much more reliable but a very small number have failed. Now it doesn't matter what your friends or anyone else says - this is an absolute fact and we have repaired them accordingly.

There is also a commonality in the failures that suggests more may follow and a correlation between the cause and age of the cars that also means more may follow. The result is advice that anyone that is used to driving flat our from cold (especially in a higher mileage older version) would be wise to be more patient and go through the warm up procedures as set down by the manufacturers. This advice is based on sound analysis of the failures we have experienced and is aimed to help more owners avoid premature failures by adhering to well documented advice about warming up engines before driving flat out. Because the evidence we have measured shows a minute but gradual stress relieving in the bottom of the cylinders that can cause the bore clearance to reduce over a long period of time - owners who may have got away with driving prematurely fast from cold for years may find it catches them out one day. I cannot see why trying to help owners by pointing out this good advice is in any way something to criticise. If you or anyone else wants to ignore this advice they are free to do so.

None of this prevents the 9A1 being a generally superbly reliable engine and a great car and similarly nothing I wrote contradicts that. If you think those simple points were riddles I guess there is nothing I can do to communicate anything meaningful to you but what I will say is hopefully very clear - however much you love this 9A1 model there are some that will have an engine failure and some specialists that are doing a very good job of fixing them when they do. Frankly I cannot find anything in that statement that requires over reaction or criticism.

Baz

 

I appreciate your patience and value this advice. Thanks.

 

This ... many times.

Few of us have the exposure or experience to look beyond our small worlds. But if we are smart we will listen to those who have broader horizons to view from.

Anything we can do to maintain the high reliability (no complex design is 100% reliable) of these 9A1 motors is good to know.

Thank you, as always, for your input.

 

Never said 9A1s don't fail, have not failed and will not fail in the future. Friends are long time Porsche techs I have known in some instances 25 years. What they are saying is no different than what you SEEM to be saying about the 9A1'. They just don't blur lines when promoting their services.

I also never said it a bad idea to follow Porsche's recommended and/or common sense warm up procedure.

 

That’s interesting Doug. Perhaps the following will explain our predicament a little better.

Having started the business mainly out of years of respect and admiration for the engineering quality that enabled a highly tuned sports car to be both reliable and exciting – it was a blow when the early Boxsters started to fail.

Back then we could not even obtain gaskets and seals to rebuild them and for those owners who had stretched their budgets to what they assumed to be an extremely reliable sports car – it was often a desperate situation finding engines from crashed cars to get them going until we eventually were able to put one back together again and started to investigate and analyse the design.It didn’t give us any pleasure to find the marque that we gave up high level careers to work with were becoming such a huge disappointment but we were happy that - with a fortunate background in racing engine design and small batch manufacture it rather fell in our lap when we could do something about it.

We initially identified the open deck cylinder design, overhung crankshaft/flywheel end and that notorious IMS bearing as very poorly thought out weaknesses while other parts (like the heavy metal inserts in the crankshaft carrier) were very good design aspects for long and reliable life without crankshaft shell fretting.

The LOKASIL silicon rich cylinder areas seemed like a great idea promoted exactly the same as the proven Alusil designs in the 944/68 until it gradually became apparent that in fact there were many more differences than that leading to failures.

Gradually other issues became important and the LTT etc all added to changes that enabled rebuilt engines to be a better specification than the originals and at a lower cost, allowing us to diversify into engine re-manufacture IN HOUSE as well as service, repairs and sales.

The turbo and GT3 M96/7 versions avoided those 3 main weaknesses having closed deck Nikasil alloy cylinders, a normal crankshaft overhang and proper IMS bearing system – as did the later 9A1 (actually removing the IMS all together).We expected later 3.2, 3.4, 3.6 and 3.8 engines to gradually eliminate these weaknesses and were even more disillusioned when cylinders became even thinner and the ferrous coated pistons (that silicon alloy cylinders need to survive were to work reliably) were changed to plastic coatings that failed even sooner.All good for our business but not for our pride and admiration for the manufacturer we originally had so much faith in – now having to deal with angry owners vowing never to buy a PORSCHE again and looking for anyone to vent their anger on including us even though we offered a very good viable solution.

Relief eventually emerged with the 9A1 having closed deck cylinders, no overhung crankshaft flywheel end, and no IMS. Our only reservation was that the return to ferrous coated pistons did not seem to have the same hard iron plating as the original 944/968 versions (that were so reliable) At last we expected to be involved in looking after cars that lived up to the image we always held dear to our hearts.So when some of those started to fail and the initial reaction was exactly the same as the previous models (denial and accusations that anyone casting any doubts on the reliability were mistaken etc etc) we wondered if there was going to be a repeat and immediately got involved in the same process of investigation to see what the likely long term outcome would be Buying a high mileage car and engine).

We were relieved that this revealed only one significant issue (we could not in all fairness call it a fault) that afflicted all 5 engines we were involved in – was that the cylinders had gradually closed in at the bottom in the thrust direction and reduced the piston clearances significantly (something almost impossible for manufacturers to discover when it takes years of heat/cool cycles to materialise). Indeed in every case owners who had previously enjoyed driving fast from cold without incidence were now unexpectedly suffering from doing exactly that as the pistons expanded quicker than the cylinders could catch up and “cold” seized.Now the dilemma – what to do about it! The technical solution was simple – new closed deck Nikasil plated cylinders (like we had already supplied in thousands with 100% reliability for many years for the M96/7 models) but the advisory issue was more challenging.

We could remind owners to be more patient in warm up and also not to expect too much from this new engine type – much more reliable ABSOLUTELY, better design YES – never ever going to fail – well that’s the problem getting over a slight word of caution and combine it with support if it did ever go wrong that a solution is available without being accused of “scare mongering” and "self-promotion".That brings us to the comments I often post just to bring a proper balance to the situation and - if at all possible - help more owners avoid premature failures.That this invokes criticism – we expected – so we try not to over-react.

Our motives are good and our experiences real but we could well have been better off avoiding any comments and simply fixing the greater number that fail as a result – but we didn’t start Hartech to earn a good or easy living (in fact we knew the opposite was likely) – we did it to enjoy our involvement with the marque we were fixated on for the later part of our working life.In view of all this it is difficult to ignore comments that are contrary to our experiences and expectations.I hope all 9A1 owners avoid problems and that all Porsche owners continue to enjoy and live the marque – and that the future holds less difficult issues with newer models than those we have had to endure in the past decade.

We might not have always got the balance right or handled the responses perfectly but is has been a much more difficult situation to manage than I for one would ever have predicted.

Baz

 

 

+1

Those claiming the engine is "bullet proof" are dreaming (and i hate that expression!!). Nothing is bullet proof

Baz points out that it is certainly a better engine design than the Gen 1 but that there are problems and that they may manifest themselves more as the cars age. I dont understand why people want to stick their heads in the sand and claim scare mongering etc when its a demonstrable issue. Its all academic until it happens to you. And it may never happen but why ignore good advice and experience and claim "my car is bullet proof"

 

Never claimed a 9A1 won't fail. Bullet proof in auto speak does not mean never fail. I have seen "bullet proof" Mezgers let go. I didn't stick my head in the sand. Sold the NA 997.2 after 6 months and went back to a turbo.

Warming car up properly before flogging it is common sense and many manufacturers electronically limit rpms until the car reaches proper running temperature.

According to the unscientific polls above, the 997.1 has about a 20% bore score failure rate (34 total), a 6% IMS failure rate (76 total) and no telling how many 997.2 people voted "no" in the IMS poll. There were 2 failures of the 997.2 in the above polls.

2 997.2 failures seems pretty bullet proof compared to 110 catastrophic 997.1 failures just of people hanging out here. That's too many. Perhaps the 9A1s will start grenading in the future at a similar rate, but they haven't yet. I would also be concerned that more 996/97s are scored or scoring, but the owners don't have clue.

Not sure about you academic comment. Makes me sick to see guys on here posting catastrophic failures, especially those trying to enjoy their first foray into the Porsche 911.

 

What it means is that everyone talks about failure rate polls etc (and the polls on here are hardly scientific) and its an interesting read until something like bore scoring happens to you, as it did to me. Then its 100% certainty

People talk about their experiences on here, thats what the forum is about. Posting about failures is part of the experience so not sure why it makes you sick. If newbies dont want to read about it then they should not read threads related to these issues and just read the posts about how the 997 is the bestest most bulletproofest engines ever made. Not to mention how raw and analogue it is

 

Interesting how your mind processed/worked through that one. I am not sick because an engine failed and heck yeah people should post about it.

I just feel bad for the guys who sustain the failures, especially those on their first 911s and those who stretched it a bit to get a 911 and do not have another $20k readily sitting around to sink into a 10 year old car not worth much more. FWIW, I felt bad for you when reading about your ordeal.

 

I'm reopening this thread again. I own a 997.2 C2S with 80000km which now is making a distinct tapping noise at cold start. Goes away after 5 minutes of driving but during the first 5 minutes you can hear it in the car while driving and engine braking, but now when accelerating. Also standing still and revving it only tapps when letting off the accelerator after you rev it. So not while revving up, only when revving down. And not on idle. The car has center muffler delete, serviced every 15000 km and running 0W-40 Mobil 1 oil, no engine mods. After the engine gets up to normal temp you can't hear the tapping while revving like in the movie below. So only when its cold.

It's currently at the local Porsche dealer and they say they can hear the tapping noise also at idle, must be with some instrument I guess or standing under the car while on the lift and idling. They have removed all 6 spark plugs and are about the check the cylinders, fingers crossed it's nothing critical.

Heres a movie:
Any ideas?

 

stand back its gonna blow!!!