Fuel pump not priming

What was the original reason you needed to replace the Engine Computer?

One of the computer's really important jobs is to turn the fuel pump off if a fuel line gets ruptured in a crash. With no fuel pressure, the engine cannot run. With a stalled engine, no signal pulses will show up from the crankshaft position sensor and/or camshaft position sensor. With those signal pulses missing, the computer knows the engine has stopped running and there is no need for fuel, so it turns the pump off so raw gas does not get dumped on the ground where it would become a serious fire hazard.

By far more problems are caused by failing sensors, and it is common for them to fail by becoming heat-sensitive, then they will work again after cooling down for about an hour. You did not provide any details as far as times or other observations or clues, but a common comment is the engine runs fine as long as the car is moving, then, after stopping for a few minutes, as in when stopping for gas, the engine will not restart for an hour. During that "hot soak", engine heat is not being blown away by natural air flow. It migrates up to the sensors causing one to fail. It commonly starts working again after about an hour.

The place to start is by having the diagnostic fault codes read and recorded. If you are lucky, there will be one related to one of those sensors, but if there is not, that is not conclusive. It can take a little time for a fault code to set related to the cam or crank sensors, and just cranking the engine in an attempt to get it started might not be enough time. This refers to a crank/no-start condition that typically includes no spark. If you have spark when the no-start occurs, and you can hear the fuel pump is not running for one second when you turn on the ignition switch, we will need to diagnose that circuit. There is multiple possible causes for the fuel pump circuit to be bad by itself. The Engine Computer would be the least likely suspect on that list.