The engine often fails to turn over with the key during warm weather. I replaced the starting motor & solinoid, & ignition switch. To start the car under those conditions I run a small wire from the solinoid and connect it to the battery for a couple of seconds and the engine never fails to turn over and run smoothly. In the colder weather I never have to use that wire. When the engine isn't turning over and starting there is absolutely no sound. It always starts with the key when I first use the car each day, regardless of the weather.