I have an 2008 Cayman S, I need new tpms sensors but I am not sure if my car is 315 mhz or 433 mhz. My car is a north american car (if that makes any difference). I have used the search but I couldn't come up with any definate answers, I found some that said 315 and some said 433 so I am even more confused now. I know someone will say call the dealer but everytime I call they send me to voicemail because there is no one at the parts counter. Thanks for any help in advance!