I have a 2002 LS 8 cylinder. In warm weather, when the car is cold, engine won't start on first crank. It takes additional 1-2 cranks to start. Then there is a fuel smell similar to paint thinner. Spoke to several mechanics who said it could be several things and it would be a trial and error type repair. Also noticed recently, in park or neutral, the engine will bog down at 3000 rpm. However while driving, there is no hesitation when accelerating to pass slower traffic. Need to fix whether I keep the vehicle or sell it and I really don't want to drop big $$ replacing parts until I get to the right one. Any ideas?????