hey guys in the morning when i start my car i let it worm up a bit then when i put in reverse it starts to idle really bad and shakes it feels like it wants to shut off but it doesn't this also happens when its on drive as im leaving for work. then it goes kinda away when im driving for like 10 mins but rough idle is still there when i come to a stop...this only happens when my car sits for a few hours and start up again??...it feels like theres a missfire but not sure what it is.any clue guys???i had my tune up done about 5k miles ago put in a reman distributor,new cap&rotor,new plugs,wires and the coil..please help any idea what it might be..thanks