i tried to start my car up after work today. I would turn the key and it would all start up, but as soon as i let the key go everything shut down. I tried again and gave it some gas, samething happened. after like 2 minutes of trying it finally started up as i revved it above 4k. What could this be? the car starts up normal after its warmed up , but if it sits for like 2 or more hours it acts up. Please help guys!