I hate to let it go at that but it really sounds like you hit it, worn or clogged control rings. If clogged due to a poor oil change schedule (previous owner), some of those restorer/ flush/ smoke stopper additives may give a result. I forget who but there is somone on here that is testing on of these and he is pretty convinced so far that it is working. Maybe someone remembers who it is and will read this. <img src="/forums/images/graemlins/kewl.gif" alt="" />