This car has met or exceeded all of my expectations. Except for today -- 600 miles on vehicle, cruising along at 70 MPH, engine malfunction light came on. Checked gas cap -- on tight and 'O' ring still new. I only use top tier 93 octane gas. I went ahead and filled up at another top tier 93 octane station -- car runs great. I put an additional 50 miles on it hoping it would clear -- light is on constant, not flashing. Any ideas I can Check? Any way to clear the light so I can see if it comes back? Thanks!