I have a 3.4, recently noticed that it is hard to start after shut-off when it's at normal temp. It cranks over but end up having to hit the gas to start, then it runs fine. It fires right up when cold or sitting for a while. I've not been able to locate any v-leaks, and the plugs and wires are fairly new, within 10 k miles. Any insight?

 

My guess would be the injectors. For some reason there's not enough fuel in the cylinders so the fuel is burning faster than the cylinder gets filled. When it's cold, the pump injects fuel into the cylinder before starting the car. Try running a good fuel treatment through the car or put in 1/3 can od Seafoam in the gas tank.