Vauxhall Corsa 1.3 CDTI 08 cutting out when starting & eng man light?

Hi all,

Hope someone is able to help.

I have a Vauxhall Corsa 1.3 CDTI 2008 (08 plate) with 53,000 miles on the clock, owned for almost 1 year, 3 previous owners, purchased from Evans Halshaw.

Approx 3/4 months ago problem started with the car not starting properly, had it into Vauxhall garage to sort, was told it was the fuel injector which was replaced. Approx 2 weeks after problem was fixed it started again, car was starting from cold but not warm. Took back to Vauxhall again this time was showing INSP2 (which I replaced faulty bulb) and straight after INSP4, but once bulb was replaced INSP4 never showed up again. Explain all this to Vauxhall. They replaced EGR valve. Problem seemed ok, several weeks later (today) I have tried to start the car, no INSP error on dash, engine management light showing, try to start the car & EML on, car splutters but does start, squeaking noise coming from somewhere, dark smoke coming out of exhaust, car stays on for 1/2 seconds then cuts out. Left for few hours and tried again and now seems to start and tick over ok, although there is a faint squecking noise. As I said I have had injector & EGR valve replaced. Does anyone know what the problem could be or offer me any advice? Why would it not start and cut out (5 times in a row) and then a few hours later start ok?

Any help would be greatfuly received!

Thanks.