We have updated reliability stats for the Boxster and Cayman that include owner experiences through December 31, 2011.
Repair frequencies, in terms of repair trips per 100 cars per year:
2008: 31, better than average
2007: 72, about average, might be high because final year of standard warranty
2006: 49, better than average
2005: 56, better than average
2004: 16, better than average, small sample size
2003: 42, better than average
2002: 97, better than average
2001: 95, better than average
2000: 100, about average
1999: 60, better 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: 72, < 1
2006: 71, 4
2005: 49, 4
2001: 42, 4
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.
Rear main seal and air/oil separator repairs remain far more common.
Thank you, once again, to 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.
To see how competitors compare, and to sign up to help improve this information:
Porsche Boxster reliability ratings and comparisons
Porsche Boxster repair odds