Sometimes when I start my engine, whether the engine is hot or cold, sometimes it starts right up and every so often, it takes longer cranking the engine to start it. Batteries and starter are good. It does not seem to crank slowly. It runs fine after started. Does anybody know why this is happening? Yes, I am waiting for the engine heater light to turn off. This was happening before and after installing the power puck. I don't have a fuel pressure guage to test it.

 

I have this same probem on my dads 06 and it is stock hope someone can answer your question.

 

If you do a search on this, there are quite a few threads on this topic.

Seems to be:
1)Lift pump
or
2)Injectors
or
3)Cam Shaft Postion sensor

 

I had the same problem. It was unpredictable in occurrence. There's a a TSB (TSB # 18-003-06 Rev A) that will address this and a few other issues.