Vocky
Just to keep you updated on this:
I refitted the egr valve and the cooling fan did not come back on for two days. So I fitted the new tested cheater started her up and the eml came on

so pulled fuse 8 for a few seconds replaced and all seems to be ok.

Three days and counting.
Hopeful problem solved possibly a faulty batch of diodes? Though I checked the resistances and diodes old vs new and they both seemed fine????
I will up date in a weeks time if no change.
Just one other thing the cars seems to take about a week to settle back down after the ecu is re-set. There are is a huge flat spot around 3500 rpm which slowly disappears over time? Is this normal?
Cheers Oakmere