We have updated reliability stats for the Boxster and Cayman that include owner experiences through September 30, 2012.
Repair frequencies, in terms of repair trips per 100 cars per year:
2008: 42, about average, stricter recalibrated scale
2007: 29, better than average
2006: 38, better than average
2005: 34, better than average
2004: 50, better than average, small sample size
2003: 46, better than average
2002: 67, better than average
2001: 80, better than average
2000: 44, better than average
1999: 117, worse than average
We have two additional statistics, "Nada-odds" and "Lemon-odds," to indicate the percentage of cars with no repairs in the past year and those that required 3+ trips to the repair shop.
For the years where we have enough data for these:
2008: 68, < 1
2006: 74, 4
2005: 78, 3
2001: 44, < 1
Important note: these cars are only driven an average of 5,500 miles a year, about half as much as the average car. No adjustment has been made for this.
Six IMS failures were reported for the 2010 calendar year, most of them for 2004-2005 model year cars (with the 2005 being a 987 rather than a 986).
No IMS failures have been reported for cars 2006 and newer.
No IMS failures have been reported for any model year since the beginning of 2011, with over 200 owners of 1999-2005 cars participating.
Update: one case of a leaking but not failed IMS reported after September 30th.
Rear main seal and air/oil separator repairs remain far more common.
We'll have further updates in February and May. We'd love to provide more precise stats and cover more model years--just a matter of getting more owners involved.
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Porsche Boxster reliability ratings and comparisons