Out of curiousity, myself and other Zetecers have noticed that our engines "whistle" or "whine". It is constantly there and gets louder and higher pitched as RPMs rise. Mine has done it almost since new, so I doubt anything is failing (@ 73k miles, it probably would have already), but I've alwasy been curious what it was. I've heard some say VCT, but don't know if that is correct or not. Any experts?
