Sometime the ignition does not start the car, no sound at all, but the power to the radio, instrument pannel is fine. When that happened, I usually had to either clutched it again OR turned the key back and restarted again, then it worked. Sometimes I had to repeat it a few times before it started, sometimes, it started the second try. I did clutched it all the way down since I've known that it could be the problem, but I do not think so. Also, the issue used to happen less frequently, now it seems to have happened more frequently. Also, it tends to happen more consistently when the car has been driven for a while (about 40mins) and then parked for a while (like few hours), then when I tried to drive it again then I could not start it the first time. Also, the weather is hot, around 90+ degrees (Los Angeles). If I drove it a while like I said above, parked, stopped the engine and tried to restart the engine immediately, then it started OK. Also, I have notice recently (by experimenting) that if I got into the car, turned the key to the right all the way without starting the engine, and let it in that state until everything the the car functions (like lights, radio, oil full meter check, etc...), then start the ignition, then more often it works the first time.
What could be the issue here? Thanks for all your help.