Intermittant starting fault

[taydb9]

I'm a new member using this forum for the first time and have been very impressed with the answers most people get. I have a problem with my fabia 1.9sdi. It has developed an intermittant starting fault, the engine turns over but won't kick in. On the three recent times this has happened I have cracked open the injector pipes and turned the engine over. There has been air in the system and after diesel starts coming through the car runs fine. I can't understand how air is getting in only when the car is not running. Does anybody have any idea what the problem could be?:confused:

[MoggyTech]

Try draining the fuel filter to remove any water from the trap. If that doesn't do it, scan for fault codes.

[taydb9]

Cheers for replying, it's had a new fuel filter to try and sort the problem out and there are no fault codes showing after a scan.

[kwacka]

Are there any plastic or rubber pipes on the spill (return) system. If they have perished they can let in air to the fuel pump when shut down - common fault on vauxhall diesels.