I know its not a Vauxhall but my work runabout is a 1997 Rover 420 GSDI. I've just done the headgasket and after reassembling everything it took me two hours to start it. This I expected as the injectors had been out so I had to bleed the fuel system.
When the car's running, everything seems fine but the car's a nightmare to start when cold and not much better when warm. I've replaced the glow plugs and still no joy. Yesterday it took me over two hours to get the thing started, all it does is turn over for ages, bellowing white smoke out the back and eventually it will start to fire, clear itself and then tick over fine. Before I took the head off, it started sweet as a nut.
Any ideas what could be the problem, Have I disturbed an injector or is it likely to be something else?
Check all your disturbed fuel system connections. Even the tiniest air leak will cause the fuel to drain back every time you stop the engine - effectively meaning, every time you start, it has to prime all over again.
Also, do check the plugs are actually glowing and they're getting current to them. They may be new, but if you've blown a fuse or messed up the timer relay somehow, they'll be about as usefull as a chocolate teapot!
I've checked the feed to the glow plugs and they're getting about 11 volts so I think they're ok. I'll double check the fuel lines for any signs of an air leak but I'm gonna take the injectors out and get them tested in case the aren't spraying properly.