Toyota auris 1.4 d4d 2009 low fuel pressure problem

[MIChAEL.S]

Hi.. i have an Auris 2009 1.4 d4d 6 speed manual (auris year model 2010) and i have one problem, especially when its cold. When it starts .. sometimes its perfect.. runs perfect .. but sometimes the rnp of the car goes up and down .. from 900rnp to 400rnp .. and turn off.. if you put the airconditioning .. the problem its bigger. The engine light its on. Also some times .. when its run .. and you are moving .. the engine light turns on.. and the engine goes off. When you are trying to start it again ... does not start. If you disconnect the Battery and put it again.. the the engine is normal again and you can turn the engine on. I put it in the computer and says that has low fuel pressure problems.. anyone has any idea what is going on ? The fuel pump metering shows 300 pressure .. and everything shows good. The strange thing is that the problem is not always ... it comes (sometimes 3-4 times a day and you must disconnect the Battery and connect it again in order to start up the engine again) and sometimes for 2-3 weeks .. their is not a problem at all ... sometimes .. every 2-3 days... 

Anyone with any answers to that ? Thanks a lot.. Michael