Porsche Boxster Running Woes

[TheFonz]

My girlfriend's father recently bought a 2002 Porsche Boxster S and is having issues getting to run properly. The car has 23,xxx miles on it. Since getting it, it has not started happily.

Symptoms-
Takes forever to start and when it does start it misfires on all cylinders-
Codes read Misfire on cylinder 2,4,5,6 and random misfire- that clears up after running for a couple of minutes.
After a couple of minutes I can erase all codes and it will run fine from there on out.

What he has done-
Replaced coils and plugs on each cylinder
Replaced all fuel injectors
Replaced Crank Position Sensor
Had ECU tested

Once warm it starts and runs fine.

Thanks