mkaresh

CR gets all of their reliability data from surveys, many of them conducted online these days. They road test cars, but these road tests are used to evaluate what the car is like to drive, not its reliability. After all, the sample size would be one.

You can collect excellent data from surveys--but they must be very carefully constructed. There are better and worse ways to word the survey and to report the results.

CR's survey is very badly worded, in a way that opens the door wide for any biases the owner might have. I've discussed this here:

Consumer Reports survey critique

In comparison, our survey is worded to keep responses as objective as possible. We also only collect data going forward, and ask for continuous participation. Other surveys are one-time and retrospectice, so it's more likely that people will only respond when they have a problem to report.

Finally, when reporting results we stick to metrics that can reliably be measured with a survey, and promptly update four times a year.

There are other differences, but these are the primary ones.

We'll have updated results for the 2009 next week. For some reason we have fewer owners signed up for the 2008--especially need more of these.

Car reliability research

u080570

Just added my A5

mkaresh

Thanks, I appreciate it.

We've updated survey results for the A5 / S5 to include owner experiences through June 2009. With a repair frequency of 41 repairs per 100 cars per year, the 2009 A4, A5, and S5 are about average.

A big thank you, once again, to JET, this forum, and everyone who has been helping. We'll have further updates in November and February. With more participants, we could provide more precise information and cover all model years. Especially need more 2008s, as the first year cannot be combined with the A4.

Audi A4 / A5 reliability comparisons

mkaresh

Updated results again later this month.

We're going to start providing new stats for the odds of requiring no repairs and the odds of getting a lemon. These require larger sample sizes, so additional participants would be helpful.

We especially need more 2008s, since the first year cars cannot be pooled with the A4.

For the details, and to sign up:

Car reliability research

mkaresh

We've updated survey results for the A5 / S5 to include owner experiences through September 30, 2009. With a repair frequency of 55 repairs per 100 cars per year, the 2009 A4, A5, and S5 are about average.

A big thank you, once again, to JET, this forum, and everyone who has been helping. We'll have further updates in February and May. With more participants, we could provide more precise information and cover all model years. Especially need more 2008s, as the first year cannot be combined with the A4.

Audi A4 / A5 reliability comparisons

Lucien4

I'm not seeing any A5 or S5 repair histories. Can you add it?

I just read how CR gets their data:
- They send annual survey to 7 million web and mag subscribers and got about 1.4 million back this year
- CR buys their own test cars and test them for several months

I think CR reliability info is decent but there's no detail and from the category stats it's hard to judge how severe or annoying issues are. I love that you can read experience and repair log on truedelta.

mkaresh

CR's reliability stats are not in any way based on their extended road tests. Instead, they're based entirely on surveys. They certainly do have plenty of responses, but weaknesses in their methodology cancel out this advantage, and then some. My detailed critique:

Consumer Reports critique

I'm not sure why you couldn't find any repair histories. They're here:

Audi A5 / S5 repair histories

I plan to provide additional information in the future--the number of owners involved is the bottleneck. As more owners join and participate, we'll be able to do more.

Lucien4

If I click on reliability (http://www.truedelta.com/car-reliability.php) then there's no A5/S5 listed in the drop-down box after choosing Audi.

So don't know how to get to repair history page (where I do see A5/S5 for some reason in the drop down box). Seems an issue with the site.

PetC

+1 Lucien4

mkaresh

Thanks for the suggestion. I usually combine similar models that share a make in the results, but can see how this might be confusing in the current case. So I've changed it to list the A5, with a dedicated page. The results are still largely based on responses for the A4, though.

We have updated survey results for the A5 / S5 to include owner experiences through December 31, 2009.

With a repair frequency of 64 repairs per 100 cars per year, the 2009 A4, A5, and S5 are about average.

The 2010s so far have 30 repairs per 100 cars per year, better than average.

A big thank you, once again, to JET, this forum, and everyone who has been helping. We'll have further updates in May and August. With more participants, we could provide more precise information and cover all model years.

Especially need more 2008s, as the first year cannot be combined with the A4. With enough participants, I'd also break out results by engine.

Audi A5 / S5 reliability comparisons