Ok guys this is my first time on this forum but I have used forums in the past to find a solution to weird issues. So here's the brain boggler I have. 92k miles NO warning lights on, first thing in the morning after sitting all night, the car will start as soon as you turn the key just as it should. You can then turn it off and then try to restart it and it will crank for 10 seconds and sounds like it has absolutely no compression before it starts and it idles rough for a few seconds once it starts. BUT, if you then turn the engine off, and then turn key to run and count to 3 then to start it will start instantly. EVERY TIME as many time as you want to try it. Once last week it failed to start even after sitting over night. Took other car to work. Came home and it started instantly and has started if you count to three ever since. Have changed fuel filter and fuel pressure regulator, with no change. I have no idea where to go from here. I can build a SB chevy with my eyes closed but have no clue when it comes to all the newer cars. Please HELP....

 

I'd suggest fuel pump.