99sebring

How long since a tune-up? When the problem is ongoing, if it cranks good but won't start, have a helper crank it while you check for spark at the plugs, if spark everywhere, use a gage and check proper fuel pressure. Also, check fuel injector pulse. Make sure battery has a full charge. Those are the basics, you have to begin testing, somewhere.

Has no codes all engine codes fixed, runs great for 20 min or so then then chugs to a stall

You need to do some testing. I can help with testing. but, you have to do the testing. Otherwise, I don't know how to help? At the moment, I don't care if there aren't any codes?

A fuel issue would not throw a code. Check the fuel pressure, may be a bad fuel pump. Make sure you can hear it prime up by having the key in the on position.