My son has a 96 Bonneville with 58,000 miles. When starting it cranks and sputters. It will stall unless the gas is pressed. Once it starts it runs and drives fine. It has stalled a few times while driving after stopping at a light. I cleaned the throttle body. Yesterday the check engine light came on. I replaced the idle control valve. I scanned it and it came back mass air flow sensor. Going to replace that tomorrow. Does this sound like a MAF sensor issue? Any other suggestions please feel free to comment.

What is the fuel pressure with the ignition on and the engine stopped?

What is the fuel pressure with the engine idling?

Has the fuel pressure regulator ever been replaced?

Unplug the MAF and see how it runs. Also tap on it while idling and if the engine stumbles the sensor is bad.

I did and it stalled out without the MAF. I’m going to replace that today.

Unplug then start it. Not while it'* running. It should die if unplugged while idling.