This is my first post so hello to you all!

My wife's 1.4 petrol Zetec started having this starting problem on Friday. It's done 54,000 miles and has up until now been superb apart from having several steering racks...

When I went out to look at it my heart sank as it sounded just like the timing belt had slipped/snapped, the engine was spinning over much more quickly so I whipped the cover off to have a look and to my amazment it was fine. Then I thought it must be flooded and indeed when I depressed the accelerator pedal fully, she eventually fired up and was fine until this morning, it happened again.

In the meantime I changed the plugs which were knackered, the leads and air filter too and it's still doing it very rarely, once every 10-20 starts.

My thoughts are that a. it could be some sort of exhaust recirculation valve sticking causing a depression somewhere? b. the valves are sticking? c. leaking injector(s) but why would they all fail at once?

This has my limited intellect stumped, please help!!