Replaced powertrain control module (PCM) and now vehicle will not start. What could be the issue?

I do not understand why codes could not be pulled. In the future you might want to go to a dealer, even though they are more expensive, to read trouble codes.

You could have;
A failled throttle position sensor
A failed crank position sensor
Failed coil
Failed fuel pump

I am providing you with a link that you can paste into your browser. it is a walk through of things to check when your car won't start. I don't know if it is going to be comprehensive enough for your situation as you had problems and never got codes and now your car won't start. So, it is hard for me not to say it will be something out of the realm of the walk through. however, to diagnsoe this kind of electrical problem you have to do a process of elimination from smallest issue on up to do it right. So, start with this and see how it goes.
Here is the link;

https://www.2carpros.com/articles/car-cranks-but-wont-start

We will be here if you still have questions.