Sorry cabriolet, I've just joined this forum and wasn't sure if I'd posted in the right place to begin with.Thanks for your reply in the other section.

Glenn. yes the leads haven't been disturbed at all and the mechanic tried swapping the coil packs and the injector rack but to no avail. Erm, I'm not sure there are any timing marks on this engine,it's locked up with special tools before the belt is changed.

1.9 xr2 on 40's The mechanic was back today and used a spark tester on each plug.He reckoned one was pulsing regularly and the rest were erratic.Fuel is there at the rack and all electrical connections have been double checked.

cabriolet said "these have throttle bodies that sometimes are not recognised by the ecu when u swap them about fit her original [to her car not the donor] throttle body yes i know its a arse to change in between the manifold but think this might be yr problem" on the Q&A section. Well we were back at it today and one thing I noticed was that the donor car had a MAF sensor on the air cleaner and a blanking plate just aft of the throttle body whereas the knackered engine has a MAP sensor at that position and the car it came out of has no MAF sensor.I'm going to swap inlet manifolds complete with throttle bodies and the little bit of harness and see if that makes a difference.
Thanks for your patience and tips guys!