I'm assuming that the engine won't start even when warm without easystart. If that's correct then it can't be the cold start system (glowplugs etc). My guess would be lack of fuel to the injection pump during starting possibly due to a sticking fuel cut off solenoid. This solenoid is mounted behind a heavy gauge steel plate at the back of the injection pump and is operated electronically via the immobiliser chip in the key. Once the engine is started with easystart the vibration probably unsticks the solenoid. Another possibility is that there may be a problem with the in-tank electric fuel pump if this vehicle is fitted with one. You can usually hear the pump run briefly after turning on the ignition. As the vehicle runs well once started I'm sure it can't be a major problem.
Dann
September 2007