I have owned my 2005 Honda Element EX since around 12,500 miles and it now has ~318,000 miles. Being a NASA / Missile Defense Engineer and Consultant and an auto enthusiast, throughout it's life I have been on point with preventive maintenance and addressing things here and there such as tires, brakes, oil, front suspension, starter, radiator (developed a small leak), dash led's, and honestly that's about it. It has been an incredible ride for many years from hauling my drum gear to gigs, my mountain bike on weekend adventures, to performing as a flexible hauler of all kinds of things for home improvement, college daughter (two) moves across multiple dorms, and so on. But alas time has come for the inevitable I guess so here it goes. The vehicle has started to maintain a high rev at start up and during driving, the valves are making a bit more noise than I am used to over the past few years, and when I started it this morning, while idling there was quite a cloud of intermittent "white"smoke from the exhaust. When I drove it a short distance it had limited power, it sputtered a bit, died on me once, then I parked it. Any ideas out there?