I have a 07 2v 4.6 and just in the past month or 2 when I first start it up for the day and put it in drive and go it hesitates like something is holding the motor back from turning freely. It only happens the frat few seconds and then it's just fine all day. It also does it after sitting while I work 10 hours. When it's doing it I can push the pedal to the ground but it acts like I'm holding the breaks for the first 3 seconds :/ any ideas? Thanks guys