Will pressure control solenoids problems always give a computer code

[rochester_ranger]

My tranny is skipping or pinging four or five times quickly when starting and I get the same feeling just before I come to a complete stop. I was thinking it might be a pressure control solenoid. I took it to autozone and the only code I'm getting has something to do with a leaky gas cap. Wouldn't I get some sort of code if it were bad?