Dont throw parts at it...
Look make the investment and get you a diagnostic tool so you can read the codes....and if you dont have one, get a Bentley manual.
I got my code reader off of EBAY. A CAN ODBII reader...
It can read all of the codes and with the bentley manual you can look up the Porsche codes.
Although my mechanic tell me that he has changed out very few O2 sensors because he has found air and vaccum leaks and also MAF problems...
However, in my case I had the 1053 and the 1276 code which pointed directly to one sensor.....$114 dollars it cost me for the OEM replacement...
But dont throw parts at it, it will only frustrate you more.
Chris
