I have been battling this bug for a couple of years now & after spending a couple grand at the local Toyota dealer with no answers I am having a go at it myself. I have replaced the Cold Start Temp Sensor & thoroughly cleaned the cold start injector. It starts like a champ & runs great when cold- after it warms up it starts acting like it's running rich and after shutdown when I go to start it might take 10 tries to get it to remain running. The fuel pressure gauge attached to the Cold Start Injector reads 40 lbs when running vs 10 lbs when it's acting up. I'm thinking fuel pressure regulator or a failing fuel pump? If so how could Parker Toyota not be able to diagnose those issues? I had to bring in my personal FSM which is ok but I have come to believe that some of the best Mechanics available are right here on MUD. Any advice or comments would be much appreciated. Thanks