996 Reliability Survey - Admin Approved!
#166
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What would be the value of knowing how many IMS failures occurred in the past? What most people most want to know is how many have been failing recently.
No one has to "scurry to the computer" to ensure that a failure is reported. Participants receive a regular email with a link to the survey. When they receive the email, they take a minute or two and fill out the survey. It's just not that complicated.
Similarly, if the car has been sold when the ex-owner receives the email they report this and any final repairs or unrepaired problems.
Because of the regular prompts provided by the emails, we get a much higher response rate than the typical survey.
It's true that I cannot speak to the past failure rate. But it's now clear that, with the Boxster, the failure rate over the past year has been just a few cars per hundred.
Bruce is partly right about the precision of this survey. We cannot report that the faiure rate is 5% vs 3% or 7%. But I think it's safe to say that, over the course of the past year, it's under 10%, and probably under 5%.
No one has to "scurry to the computer" to ensure that a failure is reported. Participants receive a regular email with a link to the survey. When they receive the email, they take a minute or two and fill out the survey. It's just not that complicated.
Similarly, if the car has been sold when the ex-owner receives the email they report this and any final repairs or unrepaired problems.
Because of the regular prompts provided by the emails, we get a much higher response rate than the typical survey.
It's true that I cannot speak to the past failure rate. But it's now clear that, with the Boxster, the failure rate over the past year has been just a few cars per hundred.
Bruce is partly right about the precision of this survey. We cannot report that the faiure rate is 5% vs 3% or 7%. But I think it's safe to say that, over the course of the past year, it's under 10%, and probably under 5%.
#167
Three Wheelin'
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Personally I am not interested in how many failed this year I'm interested in how many have failed period because the failures appear to happen at a variety of ages and mileages. I have no problem with the survey your running by the way - even if some 'experts' do. As far as I'm concerned it's a bit more information and like everything else I take it with a grain of salt.
#170
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Personally I am not interested in how many failed this year I'm interested in how many have failed period because the failures appear to happen at a variety of ages and mileages. I have no problem with the survey your running by the way - even if some 'experts' do. As far as I'm concerned it's a bit more information and like everything else I take it with a grain of salt.
Different ages is another matter--it's no longer possible to buy a 996 that's just a few years old.
I can see how it would be interesting, if not necessarily useful, to know the failure rate over time back to when the cars were new. But to do this would require doing without the methods the survey uses to prevent distorted results.
As it is, I hope it is just helpful for people to know that the failure rate over the past year is fairly low, if certainly not zero.
Also note that these were results for the 986, not the 996. Hoping to start having some for the 996 in February.
#171
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I believe what most of us want to know is how likely is our car, or one we contemplate buying, to fail. Therefore the most meaningful statistics would relate the failure rate to model year, age and mileage @ failure, and driving and service/maintenance histories (avg speed/rpms, oil-change interval and oil type used, etc.). Knowing how many have been failing recently is absolutely meaningless because of all the other variables, particularly the wide range of mileages oweing to the large number of these cars that are not daily drivers. It's incomprehensible that you don't understand that. You may be a fine and knowledgeable statistician in the sense of compiling data, and if that is your only goal, fine. Most of us would like to be able to relate, interpret, and draw conclusions from such a compilation, and unfortunately your methodology (as has been pointed out a number of times by a number of people) inhibits doing so in any meaningful way.
#173
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I believe what most of us want to know is how likely is our car, or one we contemplate buying, to fail. Therefore the most meaningful statistics would relate the failure rate to model year, age and mileage @ failure, and driving and service/maintenance histories (avg speed/rpms, oil-change interval and oil type used, etc.). Knowing how many have been failing recently is absolutely meaningless because of all the other variables, particularly the wide range of mileages oweing to the large number of these cars that are not daily drivers. It's incomprehensible that you don't understand that. You may be a fine and knowledgeable statistician in the sense of compiling data, and if that is your only goal, fine. Most of us would like to be able to relate, interpret, and draw conclusions from such a compilation, and unfortunately your methodology (as has been pointed out a number of times by a number of people) inhibits doing so in any meaningful way.
But I don't see that some overall stats without these variables are "absolutely meaningless" when the overall failure rate over the past year is just a few percent. It's not conceivable that any common factor would result in a high failure rate, at least not in the near term, when the overall failure rate is so low.
Also, you claim to want to know more, but posts like yours have the opposite effect.
#174
Parts Specialist
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know where lightning struck and how hot it was and wide it was and how long it was and how long it lasted and how bright it was and the temprature and relative humidity, barometric pressure, moon phase, sun spots, and what you ate for dinner 3 weeks ago and what "that guy over there" thinks about it will not give you any more ability to know when and where it will strike again
just accept there is no way to know and you either dont have a failure, or you do - some cars will last 1,000,000,000 miles and some wont make it 10,000 - your choice is to live with it, prevent via some sort of replacement, cover yourself with protection, dont drive it, sell it, or lay in bed and cry... in the end you just have to pick one and do it
My vote goes towards just getting a warranty and driving it till it blows the hell up - or preventing if that is not an option
just accept there is no way to know and you either dont have a failure, or you do - some cars will last 1,000,000,000 miles and some wont make it 10,000 - your choice is to live with it, prevent via some sort of replacement, cover yourself with protection, dont drive it, sell it, or lay in bed and cry... in the end you just have to pick one and do it
My vote goes towards just getting a warranty and driving it till it blows the hell up - or preventing if that is not an option
#175
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Also, you claim to want to know more, but posts like yours have the opposite effect.
#178
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This datum says the failure rate may be an estimated 5-10%... among a voluntary sample... excluding those whose engines failed before signing up... taken exclusively from people who frequent internet forums... in numbers that even with a designed sample would produce a double digit margin of error. On the basis of the latter point alone, 5% in this study could therefore mean 20%. Or nearly 0%.
Sorry, guys, but there is no way this study or any like it will give you a prediction for failure rate. Add to these statistical problems the fact that the failure rate over time for this engine very probably plots as a bell curve, and nobody but God in his heaven can tell you what your odds are of a future failure.
You know two things: Your engine will eventually fail for one reason or another. And you will eventually do the same. So go for a drive and enjoy yourself.
Sorry, guys, but there is no way this study or any like it will give you a prediction for failure rate. Add to these statistical problems the fact that the failure rate over time for this engine very probably plots as a bell curve, and nobody but God in his heaven can tell you what your odds are of a future failure.
You know two things: Your engine will eventually fail for one reason or another. And you will eventually do the same. So go for a drive and enjoy yourself.
#179
Parts Specialist
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well put its about like trying to figure either of those out.... and in the end if you could figure out exactly when your expiration date was (scientificly) that doesnt mean you wont get run over by a bus and never see the science tested
#180
Drifting
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...no more ticking-time-bomb in my car - engine replaced !!!
996 owners, in spite of attempts to derail this survey, I'd like you to participate. Right now conventional wisdom is that a 996 is a ticking time bomb. I do not believe that to be the truth. If we can gather enough data we have a shot at establishing a credible data base which 996 owners can point to and take comfort in.
I encourage you to ignore the doom-sayers and help prove the worth and value of the 996.
Thanks,
I encourage you to ignore the doom-sayers and help prove the worth and value of the 996.
Thanks,