Starting Issue
 

I have a 2016 F150, 5.0 Liter. Wondering if anyone has any ideas about this happening. If truck has been sitting for a while it starts fine. If I drive somewhere like to the store and turn it off, after short time in store and go to start the engine cranks a long time. Turn key to off position and try again, long crank again but eventually starts but not very smoothly. Obviously, something is going on. No check engine light on or error codes when I connect my diagnostic tool. Can't get to repair shop for several weeks. Would appreciate any feedback. Thanks

How many miles?

What do you mean by "not very smoothly"?

I have the same issue and eventually the pump died I think. Currently waiting for pump to show up so
I can replace.

Hard to explain Bones. I can tell it's starting to run but not like it normally does. When it finally starts like everything is firing then it runs fine. Has 75,000 miles on it

You never had an error code ES? But wouldn't it start hard every time if pump was bad? Mine only does it after I've driven it, shut down for a short period then go to start it.

I would shake the fuel tank it would start then die 5 mins later. Eventually scanner said low pressure at fuel rail. Otherwise, there is no check engine or wrench light. Do you hear your pump priming when you turn on ignition?

Update: just finished replacing fuel pump and it’s running normal again.

That's good. I'm leaning toward that's the issue. What sucks is I can't get my truck into the repair shop till the 17th. Still under warranty.

Engines that start fine cold but struggle when warm (and that do the opposite), are suffering from a hot soak or cold soak failure. Until the sensor or pump or whatever goes out, the only thing you can do is log suspected areas to check for abnormal output. As modern as vehicles are, few things are checked for alteration from typical behavior (like a pump running a hundred rpm lower than normal), they are mostly checked for 'oh ****, there's a serious problem here'.

Good luck, I hope it gets fixed soon. I had to change the pump on the sloped driveway with a full tank of gas. Let’s just say my association where I am renting did not like it and sent me a warning. Good thing ill
be out of there in a month ha