Mercedes 320 clk Intermittent starting
 

Hi
I have a merc 320 CLK 05 plate that i have been having starting problems with .. first of all it was fine then it started cutting out and not starting , called the AA who said that there was not enough fuel pressure, towed it home my mechanic came out and it started first time ,, happened a few more times so replaced fuel pump ...for a few weeks it was fine .. then happened again got it towed home .. mechanic ( who is a good friend ) looked and said there was a hole in a fuel pipe between the 2 petrol things that hold the petrol ( sorry I dont know anything about cars) and replaced it .. it has been fine for 6 months and now its starting again .. key turns wheel unlocks all lights come on ( no errors) but not starting not even a noise.. leave it a day go back it will start .. next:confused: day it wont .. Please any idea's as I love my car and dont wont to get rid but can't rely on it starting ?