Hi, I posted this last year, but maybe you haven't seen this. "Hi, Although my name is "C5 novice" I actually still drive a 2001 XSARA 2.0 HDI too. (I was thinking of getting a C5 - still a dream though). I have also had similar problems with starting as you described. It seems as if there is no fuel. I think that's because the fuel pump on top of the tank does not get the signal to pump fuel to the engine. I have had it at the dealer's 4 times, twice there was a broken wire, but the last two times it had to do with the brown relay (under the bonnet near the windscreen roughly in the middle). It seemed that if it was disconnected (pull out the red clasp and push it back in again) after a problem it reset itsself and works fine again. I don't understand why or how this happpens. Perhaps this might help someone who has the same problem." Now this problem doesn't seem to happen as I tend to put the key in the ignition and wait til the whirring noise of the fuel pump stops and the fuel gauge on the dash gets to its highest point. Then I start the engine and this has worked no problem for over a month now. Hope this helps. ATB, Peter