1998 bonneville stalls at highway speed. It has happened 3 times. RPM'* slowly decrease, then suddenly come back. After this happens 3 or 4 times, engine stops. It has started back immediately each time. Tank was ~1/4 full two of times and ~3/4 full the other. Checked trouble codes and P1404 turned. I don't know if that is related.

What trim level is your Bonneville?

It'* a good idea to add your year and trim to your signature. It helps us help you.

It is an SE

my 97 would do this and restart as I was rolling. Finally never restarted. it was the fuel pump. I'm not saying it'* the answer, just my experience with this problem.

I would definitely check your fuel pressure. And how old is the filter?