Same problem, same fix. I was also noticing less power going up hills. My car did stall out on me once when I was in start stop traffic as well. To recap my problem: a cold start would always turn over, a warm start if left for more than five minutes would turn over hard and then die, second start on warm start would almost always work, there would also be quite a bit of engine surging on warm starts. Replaced Fuel Pressure Regulator and this resolved my issue.
Make sure you bleed off all the pressure before you take it out (or wear goggles) as I got a nice eye full of gasoline.