I have heard of some cases of the timming belt auto tensioner sticking (it is a spring loaded device that automatically adjusts the belt tension according to how much or little it's being torqued). It makes a "grrrrr" sound only on decleration at about 1500 rpm. It is not something to really worry about unless you hear the grrrring noise. On cases I've heard of it's very noticeable, so you will know for sure if you have it or not. There may be a TSB for it, but it's not a recall. I may be making more of a deal about it than it really is. Since it's something I have heard of more than once, I just thought I'd let you know about it. My car hasn't had any problems and I'm at 80,000 miles. I don't think its detremental to the belt breaking prematurely, so I don't want anyone to be alarmed at this.