Runs rough at start up

Yes, this happens when the fuel pressure starts to get low due to a weak fuel pump or clogged fuel filter if your truck has one. To be sure, here is a guide on how to check the fuel pressure and instructions on how to change the fuel pump out if needed, if you are going to get a new fuel pump unit, please get an AC Delco unit from Rock auto they are a few dollars more but worth it.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

Here is how to change the fuel filter out with instructions after the fuel pump images below:

https://www.2carpros.com/articles/how-to-change-a-fuel-filter

Check out the diagrams (below). Let us know what happens and please upload pictures or videos of the problem.