My 02 seems to be idling fine but it has 90,000 miles, I was wondering if the o2 sensors and maf sensors were a preventative replacement item
Or if I should wait til there is an idle issue?
Generally no. Replace them when they fail. Our cars have very sensitive DMEs and a good sneeze by any of these sensors will trigger a CEL. No CEL means they are likely within spec.
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2009 Cayman 2.9L PDK (with a few tweaks)
PCA-GPX Chief Driving Instructor-Ret.
Well, tomorrow at 9am about 50 of us are getting together for breakfast at Frisco's Carhop in Long Beach. Come on down and hang out. You don't need to drive your Boxster and there is no membership required.