[pete]

Disconnect the pump from the injector...
there should fuel coming out the hose when
you turn the key on then it should stop after a second or so
then push the start button while the motor is cranking over
again fuel shoud come out of the hose to the injector...

if this all works as intended... remove the injector reconnect it
to the hose and crank the motor over on the start button there
should be a mist of fuel comeing out of the injector.. (hold a peice of paper in front of it see if it gets wet)
Make sure the power wires are pluged into the injector while doing this test
the injector also may need to be earthed to the motor...

If all this works fine & there is spark at the plug the next place to look
would be the crank shaft postion sencer... it is what tells the injector
when to fire a shot of fuel.. if it is not right it could be sending the shot of
fuel at the wrong time...