Thanks for that Info and it does help. I'm still out of my comfort zone with regard to data sheets and specs.
Today I managed to find a similar ECU, (don't know the full history of it). I swapped the mosfets & blown resistor over.
It doesn't start but I now have Injectors 4, 5, 6 Firing and the Fault code 30BB is eliminated. Now I have 30BA. Which points to Injectors 1, 2 & 3. We have a step forwards and a step backwards.
It takes some serious heat to lift and fit these mosfets so fitting new ones has to be worth a shot.
These IRF W644B I believe are now obsolete . I have found these at RS http://uk.rs-online.com/web/p/mosfet-tr ... s/7598949/
I need some hand holding, Would you be kind enough to take a look and hopefully confirm that these are a Viable replacement.