If you are going to have a go yourself be aware its likely to just go wrong. Not anything against your work but they are very sensitive. I've spent the past year chasing issues with dci injectors and have had nothing but grief. I would just go on ebay and search for either 'diesel doctor London' or even better 'Edinburgh diesel' and get recon units. Only 100 quid each and work like new. Just make sure you choose the ones with the correct code.
And in regards to coding which im sure you have read about, the car will work fine without it but i would recommend doing it once you have sorted all the other issues.
If you need any help let me know. I've read everything there is to read about these injection systems and im sick to death of fixing them