My 2001 convertible won't start all the time. When I turn the key, the engine 'catches' and immediately dies. It dies so quick that the gauges don't even start their 'sweep'. Sometimes it will happen 10 times before it will start and run, sometimes just once or twice, sometimes it starts first try. No pattern with warm/cold starts. It's been to the dealer three times. They have witnessed the problem, but every time they attach the diagnostic hand-held computer, the car starts and runs first time! They claim they can't fix it without using the tool and they also claim it is just a coincidence that it always starts when they attach the tool, which is logical, but... Anyone seen anything like this? Any ideas?