We have updated the reliability stats for the Boxster and Cayman to include owner experiences through March 31, 2011.
Repair frequencies, in terms of repair trips per 100 cars per year:
2008: 41, better than average
2007: 65, about average
2006: 54, better than average
2005: 73, about average
2004: 62, better than average, small sample size
2003: 65, better than average
2002: 112, about average
2001: 83, better than average
2000: 84, better than average
1999: 97, better than average, small sample size
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. None have been reported for any year since the beginning of 2011, with over 220 owners of 1999-2005 cars participating.
Rear main seal and air/oil separator repairs are far more common.
We'll have further updates in August and November. With more participants we could provide more precise information and cover all model years.
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Porsche Boxster reliability ratings and comparisons