Forbes Touts Consumer Reports: Porsches Will Last 200,000 Miles

The other day, when a popular blog mentioned that the Porsche Boxster was judged to be the car most likely to last 200,000 miles I did a double take. You don’t have to spend very much time in the comment sections of the major car blogs or on enthusiast forums to know that German cars have, at least to enthusiasts, a reputation for being prone to frequent and expensive maintenance and repair. Likewise, a simple internet search for [porsche boxster engine problems] puts paid to any notion that the average Porsche owner has an 85% chance of his or her car lasting to the 200K mark.

So I followed the link, which ended up at a Yahoo Autos page hosting a story by Hannah Elliot, originally sourced from Forbes, titled Cars That Will Make It Past 200,000 Miles. The story was picked up by blogs, Porsche fan sites, and import auto dealers’ trade groups, as well as a variety of news outlets like Yahoo and MSNBC, who added the title Porsche among road warriors that won’t die,

Ms. Elliot’s lede in the story is well written, no doubt. She starts by introducing a surprising proposition only to buttress her argument with a supposedly impeccable source:

Want a car that will last a long, long time? Buy a Porsche.

According to Consumer Reports’ latest reliability survey, all cars and SUVs made by the Stuttgart, Germany-based automaker are rated average or better when it comes to longevity. One car in particular–Porsche’s $47,600 Boxster–stands above the rest. It has the best predicted reliability of any vehicle tested by Consumer Reports this year.

I don’t know anything about Elliot beyond her writing. She seems to have at least a clue about cars and car culture, at least the carriage trade parts, but I think that if she spent more time hanging around with actual auto enthusiasts like she did in her article about muscle cars than with the T-Pains, Jeff Koonses or Ralph Laurens that she mentions in her thumbnail bio sketch, that she’d know better than to take Consumer Reports at face value, at least when it comes to Porsche reliability.

This is how a meme gets started. CR says something, a reporter picks that up and uses it as a hook for a story, other new agencies carry the story and as it proliferates through the internet the meme becomes conventional wisdom. “Hey, did you hear? Porsches are the most reliable, longest lasting cars. I read it in Forbes/Yahoo/my favorite fanboy site.”

TTAC has already looked into Consumer Reports’ somewhat dubious coverage of Porsche reliability. When CR first issued their press release, Porsche car aficionado and Dr. Ing. h.c. F. Porsche AG critic Jack Baruth e xpressed surprise at Porsche’s high rankings. Following up on Jack’s surprise, TTAC editor Michael Karesh (who operates TrueDelta, a site that directly competes with CR in terms of collecting and providing reliability statistics for car owners and buyers) looked behind the press release and into CR’s actual stats.

Michael discovered that CR was ranking the entire Porsche lineup as second best in terms of reliability when that ranking was based on the data from a single model year of a single model:

Number of 2009s with enough responses: 1

(a solid black blob for the 911)

Number of 2010s with enough responses: zero

Consumer Reports’ response to virtually any critique has long been the large size of their sample. Yet their coverage of recent Porsches is almost nonexistent. CR’s predictions are based on however many of the three most recent model years they have sufficient data for. The prediction for the 2011 Boxster is entirely based on the 2008, because that’s the only year they have enough data for. Yet the 2009 included significant revisions. They have no reliability ratings for the Panamera or the all-new Cayenne. So they have little basis for ranking the entire Porsche’s 2011 line. Even so, they rank Porsche second from the top.

So while Consumer Reports does not have any data at all on the Cayenne or Panamera, and the only 2009 or 2010 Porsche that they have sufficient data for is the ’09 911, actually rated “much worse than average”, CR gives a stellar ranking to the entire Porsche lineup, a ranking based almost solely on results for the ’08 Boxster.

What makes Elliot’s hyping of supposed Porsche durability almost ridiculous is just how the average Porsche owner uses his or her car. According to driver submitted data at TrueDelta, the average Boxster is driven only 5,000 miles a year. Two hundred thousand miles is an irrelevancy to almost all Porsche buyers.

I’m not trying to attack Hannah Elliot. She was provided with information from a seemingly reliable source. However, by not looking deeper into the statistics, or not even checking with Porsche enthusiasts, she gave Forbes’ approbation to CR’s shoddy work. She also compounded the error in saying that the Boxster had the “best predicted reliability of any vehicle tested by Consumer Reports this year.” That implies that CR’s rankings were based on tests of MY 2010 Boxsters, something that Michael has pointed out is simply not true. The error is squared by trumpeting that “all cars and SUVs made by the Stuttgart, Germany-based automaker”, were more reliable than average when CR simply doesn’t have enough data on all Porsche models to make that statement. Yahoo and MSNBC added their endorsements and now the next time one of their buddies with a Boxster complains about breaking engine shafts your average non-enthusiast will say, “What are you talking about? I read in Forbes that Consumers says that you can’t beat Porsche reliability.”